curl: CVE-2026-82208: wolfSSL CA-cache hit overrides callback

Summary With the wolfSSL backend, when CA caching is enabled and an CURLOPTSSLCTXFUNCTION callback replaces the trust store, curl can silently reinstall the cached store after the callback returns. A certificate trusted by the cached store but rejected by the callback-selected store is then...

Basecamp: Open redirect on app.hey.com bypasses HEY desktop's internal-origin allowlist and loads attacker content inside a HEY BrowserWindow

A case-sensitive URL scheme comparison flaw in the proxy image endpoint allowed open redirects on the mail service's web domain. The endpoint failed to recognize uppercase HTTPS scheme variants and redirected users to unproxied URLs instead of properly proxying them. When combined with the deskto...

PortSwigger Web Security: Burp Suite OpenAPI Event Log HTML injection triggers Windows SMB authentication

A vulnerability was discovered in Burp Suite where attacker-controlled text from an OpenAPI parser exception was inserted into the Event log HTML without proper encoding. When a user invoked a specific save function and selected the resulting Event log entry, malicious HTML tags were interpreted ...

curl: CVE-2026-87864: IMAP APPEND plus CRLF conversion command injection

Summary When CURLOPTCRLF is enabled, imapperformappend advertises the original input file size in the IMAP APPEND ... N literal but then transmits the expanded body bare LF → CRLF. The server consumes exactly N bytes as the literal, and the overflow bytes are parsed as new IMAP commands in the sa...

curl: CVE-2026-80255: secure cookie attribute bypass with tab

Summary A Set-Cookie header using HTAB horizontal tab instead of SPACE before the Secure attribute — e.g. Set-Cookie: sid=SECRET;\tSecure — causes curl to store the cookie without its Secure flag. The cookie is then sent over plaintext HTTP on subsequent requests to the same host. The...

curl: CVE-2026-82209: domain-scoped PSL domain cookie

Summary When libpsl is enabled and a response host is itself a public suffix e.g. github.io, a Set-Cookie header whose Domain attribute exactly equals that host is accepted by psliscookiedomainacceptable but stored with tailmatch = TRUE. RFC 6265 §5.3 requires this exact-match case to produce a...

curl: CVE-2026-87863: HSTS response erases persisted entries

Summary An authenticated HTTPS origin can return a Strict-Transport-Security: max-age value that Curlhstsparse accepts but curlxgmtime cannot later serialize. On 64-bit platforms, max-age=67768036190000000 produces an absolute expiry within timet range but outside struct tm's representable range...

curl: CVE-2026-87862: HSTS cache import drops longer-lived child

HSTS cache import silently drops a longer-lived child beneath an includeSubDomains parent Summary Loading an HSTS cache file or CURLOPTHSTSREADFUNCTION callback can silently discard a child entry. When a live includeSubDomains parent is imported before a longer-lived includeSubDomains child, only...

curl: 12: SASL DIGEST-MD5 does not validate the server's `rspauth` proof

Summary curl never verifies the rspauth value the server sends during SASL DIGEST-MD5 authentication. In Curlsaslcontinue lib/curlsasl.c, the SASLDIGESTMD5RESP handler unconditionally sends an empty acknowledgment without reading or checking the server's continuation data. Authentication then...

curl: 10: CURLOPT_MAXLIFETIME_CONN bypass on active HTTP/2 connections

Summary CURLOPTMAXLIFETIMECONN is not enforced when a new transfer is attached to an active multiplexed HTTP/2 connection. The connection-age eligibility check in urlmatchconn is gated behind !CONNINUSEconn, so an in-use HTTP/2 connection with spare stream capacity is accepted without any age...

curl: 46: `--libcurl` output carries `--insecure` across `--next` boundaries

Summary When --libcurl generates C source for a command that uses --next to separate multiple operations, local options from earlier operations leak into later ones. Specifically, if the first operation uses --insecure and the second does not, the generated program silently skips TLS certificate...

curl: 43: HTTP proxy CONNECT header chooses the `-OJ` filename after a redirect

Summary When curl follows an HTTPS redirect through an HTTP CONNECT proxy, a stale response code lets the proxy's CONNECT response Content-Disposition header control the local output filename. With --location --remote-name --remote-header-name, the proxy-provided filename is used for the...

curl: 34: `curl_mprintf` reads `double` for documented `long double` conversions — uninitialized value disclosure

Summary docs/libcurl/curlmprintf.md documents that the L length modifier makes floating-point conversions %f, %e, %E, %g, %G accept a long double argument. The implementation in lib/mprintf.c recognizes L and sets FLAGSLONGDOUBLE, but the conversion switch %f/%e/%E/%g/%G unconditionally selects...

curl: CVE-2026-87861: cross-origin reuse of a Negotiate connection

Summary: I found a cross-origin connection reuse flaw in lib/url.c, introduced by bd10924b4 as part of the recently announced "Patch the Planet" initiative. It causes a request for one origin to be sent on a connection that was authenticated with Negotiate for a different origin, while the...

curl: 36: HTTP upload resume offset consumed twice after early 307/308 redirect

Summary A read-backed HTTP POST using CURLOPTRESUMEFROMLARGE with a non-seekable source silently uploads the wrong data when the server returns a 307 or 308 redirect before the request body is sent. curleasyperform returns CURLEOK, so the caller cannot detect the substitution. The bug is in...

curl: 33: CONNECT_ONLY raw I/O selects wrong connection after CURLOPT_SHARE detach (incomplete fix for CVE-2020-8231)

Summary After a completed CURLOPTCONNECTONLY transfer, detaching the shared connection pool via curleasysetopteasy, CURLOPTSHARE, NULL causes curleasysend / curleasyrecv to silently operate on an unrelated connection from a different pool. Data intended for server B is sent to server A, and A's...

curl: 27: IMAP custom FETCH listing classification skips literal boundaries, enabling response desynchronization

Summary iscustomfetchlistingmatch in lib/imap.c classifies any custom FETCH whose sequence set contains : or , as a "listing." For that classification, imapstatelistsearchresp skips literal detection entirely. The ping-pong line parser then scans the server-declared literal body as IMAP protocol...

curl: 29: CURLOPT_ISSUERCERT accepts a different-key certificate when issuer metadata collides

Summary osslcheckissuer in lib/vtls/openssl.c uses X509checkissued to implement CURLOPTISSUERCERT. This OpenSSL function checks metadata subject/issuer names, key identifiers, algorithm compatibility, key usage but does not verify the certificate's cryptographic signature. A certificate with...

curl: 28: HTTP/3 UDP path ignores CURL_SOCKOPT_ALREADY_CONNECTED, reconnects callback-provided socket

Summary When CURLOPTSOCKOPTFUNCTION returns CURLSOCKOPTALREADYCONNECTED, the HTTP/3 QUIC UDP code path ignores it and calls connect anyway, silently reassociating the application-provided socket to a different peer. The TCP path has the correct check. This violates the documented callback contrac...

curl: Heap-use-after-free in CURLOPT_REFERER when passed a CURLINFO_REFERER pointer

Summary Setting CURLOPTREFERER with a pointer previously obtained from CURLINFOREFERER on the same easy handle triggers a heap-use-after-free. The CURLOPTREFERER handler frees data-state.referer line lib/setopt.c:2089 before Curlsetstropt reads from the now-dangling pointer line...

curl: Stacked --proto modifiers leave denied protocol enabled

Summary proto2num line 431–447 consumes only one leading modifier character via a switch statement. The documentation says entries may be "prefixed by zero or more modifiers." Before commit 86ac471d, a loop consumed all modifiers. The replacement switch reads only the first character. --proto...

curl: --etag-save - truncates append-redirected stdout

Summary saveetag line 267–273 calls fileno, fstat, ftruncatefd, 0 whenever the underlying fd is a regular file. It does not check OutStruct.regularfile, which is FALSE for stdout even when shell-redirected to a file. When --etag-save - is used with append redirection , an HTTP 2xx/3xx response...

curl: CVE-2026-80256: wcurl backslash bypass

A vulnerability was discovered in the wcurl script of the curl project. The vulnerability allowed an attacker-controlled URL to create a new file outside the directory chosen by a Windows user, subject to the user's filesystem permissions and the target not already existing. The vulnerability was...

curl: CVE-2026-80231: native CA store conn reuse

Summary nativecastore is in struct sslconfigdata line 73 of vtlsconfig.h, not sslprimaryconfig. matchsslprimaryconfig does not compare it. On macOS, Curlssleasyconfigcomplete line 258 auto-sets nativecastore = TRUE when no custom CA is configured — without modifying ssloptions. When CURLCABUNDLE ...

curl: CVE-2026-80230: OpenSSL pinning bypass

Summary Curlosslcheckpeercert line 4795 calls SSLget1peercertificate. When no peer certificate is available — as with anonymous cipher suites like AECDH-AES128-SHA — the function returns NULL. The subsequent guard at lines 4798–4799 checks !connconfig-verifypeer || connconfig-verifyhost; when bot...

curl: CVE-2026-80229: OpenSSL provider use-after-free

Summary When CURLOPTSSLENGINE is set e.g. "default" on OpenSSL 3.x, osslsetprovider line 1791 allocates a per-handle OSSLLIBCTX and stores it in data-state.libctx. During TLS connection setup, SSLCTXnewex line 3750 receives this library context and embeds a pointer to it inside the newly created...

curl: OpenSSL ENGINE selection omitted from mTLS connection matching

Summary When an application sets CURLOPTSSLENGINE to select an OpenSSL ENGINE for resolving ENG-type client certificate and private key identifiers, the engine selection is not included in the TLS configuration compared during connection reuse. A second easy handle with a different engine but the...

curl: Unbound cross-peer HTTP Digest challenge state

Summary When libcurl parses an HTTP Digest WWW-Authenticate challenge, it stores the realm, nonce, algorithm, and qop into the easy handle's state.digest — but does not bind that state to the peer that sent it. If the challenge is parsed but never used for output e.g. because Basic or Bearer was...

curl: ARG_CLEAR credential scrubbing wipes only UTF-8 copies on Windows Unicode builds

cleanarg operates on char str, which is the UTF-8 copy allocated by converttchartoUTF8. It has no reference to the original wchart argv element. c / toolgetparam.c:632 / static void cleanargchar str / now that getstr has copied the contents of nextarg, wipe the next argument out so that the...

curl: curl_share TOCTOU > RCE via Curl_llist _dtor Function Pointer Hijack

Summary: CURLSH the curl share handle allows multiple easy handles to share state — cookies, DNS cache, SSL sessions, connection cache — across threads. The share is protected by optional user-supplied mutex callbacks CURLSHOPTLOCKFUNC / CURLSHOPTUNLOCKFUNC. When a caller invokes curlsharesetopts...

curl: TLS session cache case-folds CA paths and bypasses the active trust profile

curl 8.21.0 case-folds the entire TLS session-cache peer key, so two distinct CA files whose Unix paths differ only by case can share a TLS session ticket. At lib/vtls/vtlsscache.c:723, curlstrequal compares keys that include case-sensitive CA, CRL, and issuer paths, even though...

AWS VDP: Unauthenticated go-httpbin servers : Leads to Cookie Tossing on *.aws.dev and Open Redirect

Multiple security vulnerabilities were identified in an unauthenticated go-httpbin server instance. An endpoint was found to accept arbitrary cookie domain parameters, allowing attacker-controlled cookies to be set across subdomains of a parent domain. This caused cookies to be delivered to...

curl: wolfSSL backend disables hostname verification when CURLOPT_SSL_VERIFYPEER is 0

Summary When curl is built against wolfSSL, setting CURLOPTSSLVERIFYPEER=0 causes a hostname-mismatched certificate to be accepted even though CURLOPTSSLVERIFYHOST remains at its default enabled setting. I built wolfSSL from source, built curl against it, and connected to a TLS server presenting ...

curl: RTSP CRLF injection in libcurl allows CURLOPT_RTSP_* values to inject commands into independent sessions

Summary libcurl's RTSP code interpolates the values of CURLOPTRTSPSTREAMURI, CURLOPTRTSPTRANSPORT, and CURLOPTRTSPSESSIONID directly into the RTSP request text with no check for embedded CR/LF, so a value containing \r\n splits one intended RTSP operation into multiple independent RTSP requests o...

curl: libcurl Digest/NTLM authentication ignores an explicit Authorization header

Summary When an application sets an explicit Authorization header via CURLOPTHTTPHEADER while libcurl also has credentials configured and HTTP Digest or NTLM authentication is selected/challenged, libcurl does not honor the application's header as a replacement — it sends its own internally...

curl: Domainless COOKIEFILE cookie leaks to unrelated IP-literal hosts

When curl loads a cookie file written as raw HTTP Set-Cookie: header lines and a line has no Domain attribute, the cookie is stored with co-domain == NULL, because a file import has no request-host to scope it to. On the send side, Curlcookiegetlist accepts any cookie in the bucket whose domain i...

Basecamp: One-click cross-account JavaScript execution steals a victim write token through Turbo pagination and unattached Active Storage HTML

A cross-account JavaScript execution vulnerability was discovered in a web application that allowed arbitrary code execution when a victim opened a crafted public board URL. An attacker with a separate account could leverage this vulnerability to steal the victim's write access token through a...

RubyGems: An organization admin can create an attacker-controlled organization owner via the gem transfer flow

An organization administrator was able to create an attacker-controlled organization owner through the gem transfer flow, bypassing the security policy that normally restricted owner role creation to existing owners. This privilege escalation allowed the attacker to remove legitimate organization...

curl: libcurl cache updates follow symlinks and truncate their targets

Summary: When curl updates an HSTS, Alt-Svc, or cookie cache, it opens the supplied path with "w" before validating it, so a symlink path can truncate the file it targets. Root cause: Curlfopen calls curlxfopenfilename, "w" before checking the path or creating the safe temporary file, and fopen...

curl: Windows SSPI connection-pool probe can reuse a connection under the wrong user

Summary : A fresh transfer can reuse a keep-alive connection authenticated under another Windows user because the SSPI isolation check trusts a connection ID that a health probe can set. Root cause : Curlcpoolconnseemshealthy calls Curlattachconnection, which sets data-state.recentconnid, while...

WordPress: Author → arbitrary file deletion anywhere on disk (site takeover) via `POST /wp/v2/media/<id>/finalize` poisoning `_wp_attachment_metadata`

A vulnerability was discovered in the WordPress media processing functionality. This vulnerability allowed an authenticated author to delete arbitrary files on the server. The vulnerability was caused by insufficient input validation in the finalizeitem function, which allowed an attacker to...

WordPress: Author → stored XSS in wp-admin: unescaped sub-size filename from attachment metadata breaks out of the `src` attribute in `get_media_item()`

A vulnerability was discovered in the WordPress media upload and finalize endpoints. An author could upload a crafted image with a malicious filename, which was then stored verbatim by the endpoint and rendered without proper escaping in the WordPress admin media library. This could allow the...

Myndr: Myndr CORS Misconfiguration

The CORS configuration on admin.myndr.net allowed any .myndr.net subdomain to read authenticated admin panel responses, including CSRF nonces and session data. This vulnerability could have been exploited to take over admin accounts...

Myndr: CORS Misconfiguration / Broken Access Control

A CORS misconfiguration was discovered on the admin panel that allowed any website hosted on a subdomain of the target organization to read authenticated admin responses, including CSRF nonces and session data. This vulnerability could have enabled full admin account takeover through a CSRF attac...

curl: CVE-2026-19931: Negotiate ambient user conn reuse

Summary On Windows with SSPI/Negotiate, curl 8.21.0 can reuse a connection authenticated with ambient credentials for a later request using different explicit credentials. In urlmatchauthnego, the credential comparison is skipped when conn-creds == NULL. This allows a connection authenticated as...

curl: URL API: triple-slash parses path segment as hostname

Summary libcurl's URL API misparses http:///host/path. Per RFC 3986, the authority between // and / is empty, so /host/path is the path. But parseurl in lib/urlapi.c treats the first segment as the hostname. On line 1087, the slash counter i reaches 3, which is within the valid 1-3 range, and hos...

curl: Cookie jar load skips public suffix check on PSL builds

On curl 8.21.0 with libpsl official curl.se 8.21.06 win64, Features: PSL, HTTP Set-Cookie: Domain=co.uk is dropped in verbose. The same cookie loaded from a Netscape jar file or a Set-Cookie: line in that file is accepted and later sent to unrelated hosts under the suffix bank.co.uk, other.co.uk...

curl: curl Missing Sec-WebSocket-Accept Verification Enables MITM WebSocket Session Hijacking

Summary curl's Curlwsaccept function in lib/ws.c processes the 101 Switching Protocols response to a client WebSocket upgrade request. RFC 6455 Section 4.1 mandates that the client MUST verify the Sec-WebSocket-Accept response header by computing the SHA-1 hash of the concatenation of the...

curl: CVE-2026-18924: HTTP/2 server push UAF

A vulnerability was discovered in libcurl versions 8.21.0 and later, where a use-after-free issue could occur in the HTTP/2 server push functionality. The vulnerability was caused by the fact that when a pushed transfer ends, the connection's pool is not properly handled, leading to the freed...

MariaDB: Heap Use-After-Free in Materialized_cursor::open via SYS_REFCURSOR Array Reallocation

A heap-use-after-free vulnerability was identified in the cursor handling mechanism of the database server. The vulnerability existed in the cursor opening function where array reallocation during nested cursor operations caused dangling pointer references. When a cursor's SELECT statement invoke...