Июльский Linux Patch Wednesday

July Linux Patch Wednesday. A total of 2,017 vulnerabilities were addressed 539 in the Linux kernel and 504 in Chromium. For comparison, there were 1,888 vulnerabilities in June. Once again, a new record. Moreover, next month will most likely set another record, as 1,704 vulnerabilities have...

libssh2: libssh2: Arbitrary code execution via heap buffer overflow during SSH negotiation

A flaw was found in libssh2. A malicious SSH server can exploit a pre-authentication heap buffer overflow vulnerability by sending a specially crafted packet during the Encrypt-then-MAC ETM cipher negotiation. This allows the server to corrupt heap memory, potentially leading to arbitrary code...

libssh2: libssh2: Arbitrary code execution via double-free in SFTP session

A flaw was found in libssh2. A malicious SSH Secure Shell server can exploit a double-free vulnerability in the sftpopen function. This flaw allows the server to corrupt the heap memory of an authenticated client when it opens an SFTP SSH File Transfer Protocol session. This heap corruption can...

CVE-2026-66035 libssh2 Heap Buffer Overflow via ETM Cipher Negotiation

libssh2 through 1.11.1, fixed in commit 42e33d8, contains a pre-authentication heap buffer overflow vulnerability that allows a malicious SSH server to corrupt heap metadata in any connecting client by sending a packet with a packetlength smaller than the cipher's block size during Encrypt-then-M...

EUVD-2026-48720

libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2ciphercrypt function in src/openssl.c that allows a malicious SSH server to crash any connecting client by negotiating AES-GCM ciphers during handshake. Attackers can exploit...

SUSE CVE-2026-59846

A flaw was found in libssh. A malicious username expanded through %r in ProxyCommand handling can inject shell metacharacters, exposing environment variables and causing unintended shell behavior...

CVE-2026-59851

A flaw was found in libssh. On servers with GSSAPIKeyExchange enabled, the gssapi-keyex path does not verify whether the authenticated Kerberos principal is authorized for the requested local user, allowing authenticated clients to log in as arbitrary users...

EUVD-2026-46266

A flaw was found in libssh. If data packets are processed after a channel is closed, channel data callbacks can be invoked after the associated data has already been freed, leading to crashes or possible use-after-free conditions...

EulerOS Virtualization 2.10.1 : libssh2 (EulerOS-SA-2026-2827)

According to the versions of the libssh2 package installed, the EulerOS Virtualization installation on the remote host is affected by the following vulnerabilities : A security vulnerability has been detected in libssh2 up to 1.11.1. The impacted element is the function userauthpassword of the fi...

PT-2026-61940

Name of the Vulnerable Software and Affected Versions libssh affected versions not specified Description A flaw exists where a malicious SFTP server can send responses for unknown request IDs. The libssh client queues these responses indefinitely, leading to unbounded memory growth and a...

RHEL 9 : buildah (RHSA-2026:37410)

The remote Redhat Enterprise Linux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:37410 advisory. The buildah package provides a tool for facilitating building OCI container images. Among other things, buildah enables you to: Create a...

AlmaLinux 10 : buildah (ALSA-2026:36199)

The remote AlmaLinux 10 host has packages installed that are affected by multiple vulnerabilities as referenced in the ALSA-2026:36199 advisory. golang.org/x/crypto/ssh: golang: golang.org/x/crypto/ssh: Denial of Service via crafted SSH certificate CVE-2026-39835 golang.org/x/crypto/ssh:...

UBUNTU-CVE-2026-58051

libssh2 through 1.11.1 grows its publickey list with SSH2REALLOC but does not zero-initialize new entries before parsing populates them, so a parse failure reaching the cleanup path leaves libssh2publickeylistfree operating on an uninitialized entry. A malicious SSH server offering the publickey...

OPENSUSE-SU-2026:21069-1 Security update for google-guest-agent

This update for google-guest-agent fixes the following issues - CVE-2026-33186: google.golang.org/grpc: authorization bypass due to improper validation of the HTTP/2 :path pseudo- header bsc1260264. - CVE-2026-39821: golang.org/x/net/idna: failure to reject ASCII-only Punycode-encoded labels allo...

GHSA-VGWF-H737-FF37 golang.org/x/crypto: Invoking client can cause server deadlock on unexpected responses

A malicious SSH peer could send unsolicited global request responses to fill an internal buffer, blocking the connection's read loop. The blocked goroutine could not be released by calling Close, resulting in a resource leak per connection. Unsolicited global responses are now discarded...

golang.org/x/crypto is vulnerable to invoking server panic during CheckHostKey/Authenticate flow

SSH servers which use CertChecker as a public key callback without setting IsUserAuthority or IsHostAuthority could be caused to panic by a client presenting a certificate. CertChecker now returns an error instead of panicking when these callbacks are nil...

Astra Linux – Vulnerability in libssh

A flaw was discovered in libssh, where it may attempt to open arbitrary files during configuration parsing. A local attacker can exploit this by providing a malicious configuration file or when the system is misconfigured. This vulnerability could lead to a Denial of Service DoS attack, as the...

OPENSUSE-SU-2026:11109-1 libssh2-1-1.11.1-3.1 on GA media

These are all security issues fixed in the libssh2-1-1.11.1-3.1 package on the GA media of openSUSE Tumbleweed...

CVE-2026-48110

CVE-2026-48110 affects Russh, a Rust SSH client/server library. From 0.34.0 up to before 0.61.0, several client/server message handlers decoded attacker-controlled SSH strings, name-lists, and byte fields into owned allocations before applying field-specific bounds. A remote SSH peer could send o...

CVE-2026-46673 Russh: Unchecked CryptoVec allocation and growth handling is reachable from local agent inputs in current russh releases and from remote SSH traffic in historical pre-0.58.0 releases

Russh is a Rust SSH client & server library. Prior to version 0.60.3, CryptoVec used unchecked capacity growth, unchecked length arithmetic, and unsafe allocation/locking paths. In current russh releases, local SSH agent peers could still feed attacker-controlled frame lengths into buffer growth...