Security update for dovecot23 (moderate)

An update that solves two vulnerabilities, contains one
feature and has one errata is now available.

Description:

This update for dovecot23 fixes the following issues:

Update dovecot to version 2.3.15 (jsc#SLE-19970):

Security issues fixed:

• CVE-2021-29157: Dovecot does not correctly escape kid and azp fields in
  JWT tokens. This may be used to supply attacker controlled keys to
  validate tokens, if attacker has local access. (bsc#1187418) Local
  attacker can login as any user and access their emails
• CVE-2021-33515: On-path attacker could have injected plaintext commands
  before STARTTLS negotiation that would be executed after STARTTLS
  finished with the client. (bsc#1187419) Attacker can potentially steal
  user credentials and mails

• Disconnection log messages are now more standardized across services.
  They also always now start with “Disconnected” prefix.
• Dovecot now depends on libsystemd for systemd integration.
• Removed support for Lua 5.2. Use version 5.1 or 5.3 instead.
• config: Some settings are now marked as “hidden”. It’s discouraged to
  change these settings. They will no longer be visible in doveconf
  output, except if they have been changed or if doveconf -s parameter is
  used. See https://doc.dovecot.org/settings/advanced/ for details.
• imap-compress: Compression level is now algorithm specific. See
  https://doc.dovecot.org/settings/plugin/compress-plugin/
• indexer-worker: Convert “Indexed” info logs to an event named
  “indexer_worker_indexing_finished”. See
  https://doc.dovecot.org/admin_manual/list_of_events/#indexer-worker-indexin
  g-finished

• Add TSLv1.3 support to min_protocols.
• Allow configuring ssl_cipher_suites. (for TLSv1.3+)
• acl: Add acl_ignore_namespace setting which allows to entirely ignore
  ACLs for the listed namespaces.
• imap: Support official RFC8970 preview/snippet syntax. Old methods of
  retrieving preview information via IMAP commands (“SNIPPET and PREVIEW
  with explicit algorithm selection”) have been deprecated.
• imapc: Support INDEXPVT for imapc storage to enable private message
  flags for cluster wide shared mailboxes.
• lib-storage: Add new events: mail_opened, mail_expunge_requested,
  mail_expunged, mail_cache_lookup_finished. See
  https://doc.dovecot.org/admin_manual/list_of_events/#mail
• zlib, imap-compression, fs-compress: Support compression levels that the
  algorithm supports. Before, we would allow hardcoded value between 1 to
  9 and would default to 6. Now we allow using per-algorithm value range
  and default to whatever default the algorithm specifies.

• *-login: Commands pipelined together with and just after the
  authenticate command cause these commands to be executed twice. This
  applies to all protocols that involve user login, which currently
  comprises of imap, pop3, submisision and managesieve.
• *-login: Processes are supposed to disconnect the oldest non-logged in
  connection when process_limit was reached. This didn’t actually happen
  with the default “high-security mode” (with service_count=1) where each
  connection is handled by a separate process.
• *-login: When login process reaches client/process limits, oldest client
  connections are disconnected. If one of these was still doing anvil
  lookup, this caused a crash. This could happen only if the login process
  limits were very low or if the server was overloaded.
• Fixed building with link time optimizations (-flto).
• auth: Userdb iteration with passwd driver does not always return all
  users with some nss drivers.
• dsync: Shared INBOX not synced when “mail_shared_explicit_inbox” was
  disabled. If a user has a shared mailbox which is another user’s INBOX,
  dsync didn’t include the mailbox in syncing unless explicit naming is
  enabled with “mail_shared_explicit_inbox” set to “yes”.
• dsync: Shared namespaces were not synced with “-n” flag.
• dsync: Syncing shared INBOX failed if mail_attribute_dict was not set.
  If a user has a shared mailbox that is another user’s INBOX, dsync
  failed to export the mailbox if mail attributes are disabled.
• fts-solr, fts-tika: Using both Solr FTS and Tika may have caused HTTP
  requests to assert-crash: Panic: file http-client-request.c: line 1232
  (http_client_request_send_more): assertion failed: (req->payload_input
  != NULL)
• fts-tika: 5xx errors returned by Tika server as indexing failures.
  However, Tika can return 5xx for some attachments every time. So the 5xx
  error should be retried once, but treated as success if it happens on
  the retry as well. v2.3 regression.
• fts-tika: v2.3.11 regression: Indexing messages with fts-tika may have
  resulted in Panic: file message-parser.c: line 802
  (message_parser_deinit_from_parts): assertion failed:
  (ctx->nested_parts_count == 0 || i_stream_have_bytes_left(ctx->input))
• imap: SETMETADATA could not be used to unset metadata values. Instead
  NIL was handled as a “NIL” string. v2.3.14 regression.
• imap: IMAP BINARY FETCH crashes at least on empty base64 body: Panic:
  file index-mail-binary.c: line 358 (blocks_count_lines): assertion
  failed: (block_count == 0 || block_idx+1 == block_count)
• imap: If IMAP client using the NOTIFY command was disconnected while
  sending FETCH notifications to the client, imap could crash with Panic:
  Trying to close mailbox INBOX with open transactions.
• imap: Using IMAP COMPRESS extension can cause IMAP connection to hang
  when IMAP commands are >8 kB long.
• imapc: If remote server sent BYE but didn’t immediately disconnect, it
  could cause infinite busy-loop.
• lib-index: Corrupted cache record size in dovecot.index.cache file could
  have caused a crash (segfault) when accessing it.
• lib-oauth2: JWT token time validation now works correctly with 32-bit
  systems.
• lib-ssl-iostream: Checking hostnames against an SSL certificate was
  case-sensitive.
• lib-storage: Corrupted mime.parts in dovecot.index.cache may have
  resulted in Panic: file imap-bodystructure.c: line 206
  (part_write_body): assertion failed: (text == ((part->flags &
  MESSAGE_PART_FLAG_TEXT) != 0))
• lib-storage: Index rebuilding (e.g. via doveadm force-resync) didn’t
  preserve the “hdr-pop3-uidl” header. Because of this, the next pop3
  session could have accessed all of the emails’ metadata to read their
  POP3 UIDL (opening dbox files).
• listescape: When using the listescape plugin and a shared namespace the
  plugin didn’t work properly anymore resulting in errors like: “Invalid
  mailbox name: Name must not have ‘/’ character.”
• lmtp: Connection crashes if connection gets disconnected due to multiple
  bad commands and the last bad command is BDAT.
• lmtp: The Dovecot-specific LMTP parameter XRCPTFORWARD was blindly
  forwarded by LMTP proxy without checking that the backend has support.
  This caused a command parameter error from the backend if it was running
  an older Dovecot release. This could only occur in more complex setups
  where the message was proxied twice; when the proxy generated the
  XRCPTFORWARD parameter itself the problem did not occur, so this
  only happened when it was forwarded.
• lmtp: The LMTP proxy crashes with a panic when the remote server replies
  with an error while the mail is still being forwarded through a
  DATA/BDAT command.
• lmtp: Username may have been missing from lmtp log line prefixes when it
  was performing autoexpunging.
• master: Dovecot would incorrectly fail with haproxy 2.0.14 service
  checks.
• master: Systemd service: Dovecot announces readiness for accepting
  connections earlier than it should. The following environment variables
  are now imported automatically and can be omitted from
  import_environment setting: NOTIFY_SOCKET LISTEN_FDS LISTEN_PID.
• master: service { process_min_avail } was launching processes too slowly
  when master was forking a lot of processes.
• util: Make the health-check.sh example script POSIX shell compatible.

• Added new aliases for some variables. Usage of the old ones is possible,
  but discouraged. (These were partially added already to v2.3.13.) See
  https://doc.dovecot.org/configuration_manual/config_file/config_variables/
  for more information.
• Optimize imap/pop3/submission/managesieve proxies to use less CPU at the
  cost of extra memory usage.
• Remove autocreate, expire, snarf and mail-filter plugins.
• Remove cydir storage driver.
• Remove XZ/LZMA write support. Read support will be removed in future
  release.
• doveadm -D: Add timestamps to debug output even when
  LOG_STDERR_TIMESTAMP environment variable is not set. Timestamp format
  is taken from log_timestamp setting.
• If BROKENCHAR or listescape plugin is used, the escaped folder names may
  be slightly different from before in some situations. This is unlikely
  to cause issues, although caching clients may redownload the folders.
• imapc: It now enables BROKENCHAR=~ by default to escape remote folder
  names if necessary. This also means that if there are any ‘~’ characters
  in the remote folder names, they will be visible as “~7e”.
• imapc: When using local index files folder names were escaped on
  filesystem a bit differently. This affects only if there are folder
  names that actually require escaping, which isn’t so common. The old
  style folders will be automatically deleted from filesystem.
• stats: Update exported metrics to be compliant with OpenMetrics standard.

• doveadm: Add an optional ‘-p’ parameter to metadata list command. If
  enabled, “/private”, and “/shared” metadata prefixes will be prepended
  to the keys in the list output.
• doveconf: Support environment variables in config files. See
  https://doc.dovecot.org/configuration_manual/config_file/config_file_syntax
  /#environment-variables for more details.
• indexer-worker: Change indexer to disconnect from indexer-worker after
  each request. This allows service indexer-worker’s service_count &
  idle_kill settings to work. These can be used to restart indexer-worker
  processes once in a while to reduce their memory usage.

• auth: “nodelay” with various authentication mechanisms such as apop and
  digest-md5 crashed AUTH process if authentication failed.
• auth: Auth lua script generating an error triggered an assertion
  failure: Panic: file db-lua.c: line 630 (auth_lua_call_password_verify):
  assertion failed: (lua_gettop(script->L) == 0).
• configure: Fix libunwind detection to work on other than x86_64 systems.
• doveadm-server: Process could crash if logging was done outside command
  handling. For example http-client could have done debug logging
  afterwards, resulting in either segfault or Panic: file http-client.c:
  line 642 (http_client_context_close): assertion failed:
  (cctx->clients_list == NULL).
• dsync: Folder name escaping with BROKENCHAR didn’t work completely
  correctly. This especially caused problems with dsync-migrations using
  imapc where some of the remote folder names may not have been accessible.
• dsync: doveadm sync + imapc doesn’t always sync all mails when doing an
  incremental sync (-1), which could lead to mail loss when it’s used for
  migration. This happens only when GUIDs aren’t used (i.e. imapc without
  imapc_features=guid-forced).
• fts-tika: When tika server returns error, some mails cause Panic: file
  message-parser.c: line 802 (message_parser_deinit_from_parts): assertion
  failed: (ctx->nested_parts_count == 0 ||
  i_stream_have_bytes_left(ctx->input))
• lib-imap: imapc parsing illegal BODYSTRUCTUREs with NILs could have
  resulted in crashes. This exposed that Dovecot was wrongly accepting
  atoms in “nstring” handling. Changed the IMAP parsing to be more strict
  about this now.
• lib-index: If dovecot.index.cache has corrupted message size, fetching
  BODY/BODYSTRUCTURE may cause assert-crash: Panic: file index-mail.c:
  line 1140 (index_mail_parse_body_finish): assertion failed:
  (mail->data.parts != NULL).
• lib-index: Minor error handling and race condition fixes related to
  rotating dovecot.index.log. These didn’t usually cause problems, unless
  the log files were rotated rapidly.
• lib-lua: Lua scripts using coroutines or lua libraries using coroutines
  (e.g., cqueues) panicked.
• Message PREVIEW handled whitespace wrong so first space would get eaten
  from between words.
• FTS and message PREVIEW (snippet) parsed HTML &entities case-sensitively.
• lib-mail: When max nested MIME parts were reached, IMAP BODYSTRUCTURE
  was written in a way that may have caused confusion for IMAP clients and
  also Dovecot itself when parsing it. The truncated part is now written
  out using application/octet-stream MIME type.
• lib-oauth2: HS512 and HS384 JWT token algorithms crash when you try to
  use them: Panic: file hmac.c: line 26 (hmac_init): assertion failed:
  (meth->context_size <= MAC_MAX_CONTEXT_SIZE).
• event filters: NOT keyword did not have the correct associativity.
• Ignore ECONNRESET when closing socket. This avoids logging useless
  errors on systems like FreeBSD.
• event filters: event filter syntax error may lead to Panic: file
  event-filter.c: line 137 (event_filter_parse): assertion failed:
  (state.output == NULL)
• lib: timeval_cmp_margin() was broken on 32-bit systems. This could
  potentially have caused HTTP timeouts to be handled incorrectly.
• log: instance_name wasn’t used as syslog ident by the log process.
• master: After a service reached process_limit and client_limit, it could
  have taken up to 1 second to realize that more client connections became
  available. During this time client connections could have been
  unnecessarily rejected and a warning logged: Warning: service(…):
  process_limit (…) reached, client connections are being dropped
• stats: Crash would occur when generating openmetrics data for metrics
  using aggregating functions.
• stats: Event filters comparing against empty strings crash the stats
  process.

• CVE-2020-24386: Specially crafted command can cause IMAP hibernate to
  allow logged in user to access other people’s emails and filesystem
  information.
• Metric filter and global event filter variable syntax changed to a
  SQL-like format. See
  https://doc.dovecot.org/configuration_manual/event_filter/
• auth: Added new aliases for %{variables}. Usage of the old ones is
  possible, but discouraged.
• auth: Removed RPA auth mechanism, SKEY auth mechanism, NTLM auth
  mechanism and related password schemes.
• auth: Removed passdb-sia, passdb-vpopmail and userdb-vpopmail.
• auth: Removed postfix postmap socket

• auth: Added new fields for auth server events. These fields are now also
  available for all auth events. See
  https://doc.dovecot.org/admin_manual/list_of_events/#authentication-server
  for details.
• imap-hibernate: Added imap_client_hibernated, imap_client_unhibernated
  and imap_client_unhibernate_retried events. See
  https://doc.dovecot.org/admin_manual/list_of_events/ for details.
• lib-index: Added new mail_index_recreated event. See
  https://doc.dovecot.org/admin_manual/list_of_events/#mail-index-recreated
• lib-sql: Support TLS options for cassandra driver. This requires
  cpp-driver v2.15 (or later) to work reliably.
• lib-storage: Missing $HasAttachment / $HasNoAttachment flags are now
  added to existing mails if mail_attachment_detection_option=add-flags
  and it can be done inexpensively.
• login proxy: Added login_proxy_max_reconnects setting (default 3) to
  control how many reconnections are attempted.
• login proxy: imap/pop3/submission/managesieve proxying now supports
  reconnection retrying on more than just connect() failure. Any error
  except a non-temporary authentication failure will result in reconnect
  attempts.

• auth: Lua passdb/userdb leaks stack elements per call, eventually
  causing the stack to become too deep and crashing the auth or
  auth-worker process.
• auth: SASL authentication PLAIN mechanism could be used to trigger read
  buffer overflow. However, this doesn’t seem to be exploitable in any way.
• auth: v2.3.11 regression: GSSAPI authentication fails because dovecot
  disallows NUL bytes for it.
• dict: Process used too much CPU when iterating keys, because each key
  used a separate write() syscall.
• doveadm-server: Crash could occur if logging was done outside command
  handling. For example http-client could have done debug logging
  afterwards, resulting in either segfault or Panic: file http-client.c:
  line 642 (http_client_context_close): assertion failed:
  (cctx->clients_list == NULL).
• doveadm-server: v2.3.11 regression: Trying to connect to doveadm server
  process via starttls assert-crashed if there were no ssl=yes listeners:
  Panic: file master-service-ssl.c: line 22 (master_service_ssl_init):
  assertion failed: (service->ssl_ctx_initialized).
• fts-solr: HTTP requests may have assert-crashed: Panic: file
  http-client-request.c: line 1232 (http_client_request_send_more):
  assertion failed: (req->payload_input != NULL)
• imap: IMAP NOTIFY could crash with a segmentation fault due to a bad
  configuration that causes errors. Sending the error responses to the
  client can cause the segmentation fault. This can for example happen
  when several namespaces use the same mail storage location.
• imap: IMAP NOTIFY used on a shared namespace that doesn’t actually exist
  (e.g. public namespace for a nonexistent user) can crash with a panic:
  Panic: Leaked view for index /tmp/home/asdf/mdbox/dovecot.list.index:
  Opened in (null):0
• imap: IMAP session can crash with QRESYNC extension if many changes are
  done before asking for expunged mails since last sync.
• imap: Process might hang indefinitely if client disconnects after
  sending some long-running commands pipelined, for example FETCH+LOGOUT.
• lib-compress: Mitigate crashes when configuring a not compiled in
  compression. Errors with compression configuration now distinguish
  between not supported and unknown.
• lib-compression: Using xz/lzma compression in v2.3.11 could have written
  truncated output in some situations. This would result in “Broken pipe”
  read errors when trying to read it back.
• lib-compression: zstd compression could have crashed in some situations:
  Panic: file ostream.c: line 287 (o_stream_sendv_int): assertion failed:
  (!stream->blocking)
• lib-dict: dict client could have crashed in some rare situations when
  iterating keys.
• lib-http: Fix several assert-crashes in HTTP client.
• lib-index: v2.3.11 regression: When mails were expunged at the same time
  as lots of new content was being saved to the cache (e.g. cache file was
  lost and is being re-filled) a deadlock could occur with
  dovecot.index.cache / dovecot.index.log.
• lib-index: v2.3.11 regression: dovecot.index.cache file was being purged
  (rewritten) too often when it had a field that hadn’t been accessed for
  over 1 month, but less than 2 months. Every cache file change caused a
  purging in this situation.
• lib-mail: MIME parts were not returned correctly by Dovecot MIME parser.
  Regression caused by fixing CVE-2020-12100.
• lib-mail: When max nested MIME parts were reached, IMAP BODYSTRUCTURE
  was written in a way that may have caused confusion for both IMAP
  clients and Dovecot itself when parsing it. The truncated part is now
  written out using application/octet-stream MIME type.
• lib-mail: v2.3.11 regression: Mail delivery / parsing crashed when the
  10000th MIME part was message/rfc822 (or if parent was
  multipart/digest): Panic: file message-parser.c: line 167
  (message_part_append): assertion failed: (ctx->total_parts_count <=
  ctx->max_total_mime_parts).
• lib-oauth2: Dovecot incorrectly required oauth2 server introspection
  reply to contain username with invalid token.
• lib-ssl-iostream, lib-dcrypt: Fix building with OpenSSL that has
  deprecated APIs disabled.
• lib-storage: When mail’s size is different from the cached one (in
  dovecot.index.cache or Maildir S=size in the filename), this is handled
  by logging “Cached message size smaller/larger than expected” error.
  However, in some situations this also ended up crashing with: Panic:
  file istream.c: line 315 (i_stream_read_memarea): assertion failed:
  (old_size <= _stream->pos - _stream->skip).
• lib-storage: v2.3 regression: Copying/moving mails was taking much more
  memory than before. This was mainly visible when copying/moving
  thousands of mails in a single transaction.
• lib-storage: v2.3.11 regression: Searching messages assert-crashed
  (without FTS): Panic: file message-parser.c: line 174
  (message_part_finish): assertion failed: (ctx->nested_parts_count > 0).
• lib: Dovecot v2.3 moved signal handlers around in ioloops, causing more
  CPU usage than in v2.2.
• lib: Fixed JSON parsing: '' escape sequence may have wrongly resulted
  in error if it happened to be at read boundary. Any NUL characters and
  ‘\u0000’ will now result in parsing error instead of silently truncating
  the data.
• lmtp, submission: Server may hang if SSL client connection disconnects
  during the delivery. If this happened repeated, it could have ended up
  reaching process_limit and preventing any further lmtp/submission
  deliveries.
• lmtp: Proxy does not always properly log TLS connection problems as
  errors; in some cases, only a debug message is logged if enabled.
• lmtp: The LMTP service can hang when commands are pipelined. This can
  particularly occur when one command in the middle of the pipeline fails.
  One example of this occurs for proxied LMTP transactions in which the
  final DATA or BDAT command is pipelined after a failing RCPT command.
• login-proxy: The login_source_ips setting has no effect, and therefore
  the proxy source IPs are not cycled through as they should be.
• master: Process was using 100% CPU in some situations when a broken
  service was being throttled.
• pop3-login: POP3 login would fail with “Input buffer full” if the
  initial response for SASL was too long.
• stats: Crash would occur when generating openmetrics data for metrics
  using aggregating functions.

Update pigeonhole to version 0.5.15

• CVE-2020-28200: Sieve interpreter is not protected against abusive
  scripts that claim excessive resource usage. Fixed by limiting the user
  CPU time per single script execution and cumulatively over several
  script runs within a configurable timeout period. Sufficiently large CPU
  time usage is summed in the Sieve script binary and execution is blocked
  when the sum exceeds the limit within that time. The block is lifted
  when the script is updated after the resource usage times out.
  (bsc#1187420) Attacker can DoS the mail delivery system (jsc#PM-2746)
  ECO: Dovecot 2.3.15 version upgrade
• Disconnection log messages are now more standardized across services.
  They also always now start with “Disconnected” prefix.
• managesieve: Commands pipelined together with and just after the
  authenticate command cause these commands to be executed twice.
• duplicate: The test was handled badly in a multiscript (sieve_before,
  sieve_after) scenario in which an earlier script in the sequence with a
  duplicate test succeeded, while a later script caused a runtime failure.
  In that case, the message is recorded for duplicate tracking, while the
  message may not actually have been delivered in the end.
• editheader: Sieve interpreter entered infinite loop at startup when the
  “editheader” configuration listed an invalid header name. This problem
  can only be triggered by the administrator.
• relational: The Sieve relational extension can cause a segfault at
  compile time. This is triggered by invalid script syntax. The segfault
  happens when this match type is the last argument of the test command.
  This situation is not possible in a valid script; positional arguments
  are normally present after that, which would prevent the segfault.
• sieve: For some Sieve commands the provided mailbox name is not properly
  checked for UTF-8 validity, which can cause assert crashes at runtime
  when an invalid mailbox name is encountered. This can be caused by the
  user by writing a bad Sieve script involving the affected commands
  (“mailboxexists”, “specialuse_exists”). This can be triggered by the
  remote sender only when the user has written a Sieve script that passes
  message content to one of the affected commands.
• sieve: Large sequences of 8-bit octets passed to certain Sieve commands
  that create or modify message headers that allow UTF-8 text (vacation,
  notify and addheader) can cause the delivery or IMAP process (when
  IMAPSieve is used) to enter a memory-consuming semi-infinite loop that
  ends when the process exceeds its memory limits. Logged in users can
  cause these hangs only for their own processes.

Patch Instructions:

To install this openSUSE Security Update use the SUSE recommended installation methods
like YaST online_update or “zypper patch”.

Alternatively you can run the command listed for your product:

• openSUSE Leap 15.3:

  zypper in -t patch openSUSE-SLE-15.3-2021-2892=1