Libssh 0 12 2

[chcg]

libssh 0.12.2 security release

Following up from the last week release, we managed to miss one of the fixes for GHSA-4846-7xwg-pw5m so this is a fixup release including this missing commit and few more bugfixes. The version 0.11.5 already includes the fix for this CVE.

For those new to libssh, we recommend checking out our getting started tutorial. If you have any questions, feel free to join our mailing list or visit our Matrix channel.

You can download libssh-0.12.2 here.
ChangeLog for libssh 0.12.2:
Security:

https://github.com/advisories/GHSA-4846-7xwg-pw5m: Denial of service via zero advertised channel packet size

Bugfixes:

Fix fallback to default provider if FIPS provider does not have ML-KEM implementation
Do not override explicitly set options through a configuration file to match OpenSSH behavior.
Return SSH_KNOWN_HOSTS_UNKNOWN when GSSAPI key exchange is used without any hostkey

New API:

API to check the GSSAPI key exchange was used for hostkey handling
API to initiate GSSAPI keyex authentication (missing from last release)

libssh 0.12.1 and 0.11.5 security releases

Within the storm of AI-assisted reports, we are pleased to announce another libssh releases, bringing mostly security relevant fixes for both new features and code that was used for years.

A big thank you to all the security researchers who responsibly reported the issues to us, as well as to all the contributors who made this release possible!

For those new to libssh, we recommend checking out our getting started tutorial. If you have any questions, feel free to join our mailing list or visit our Matrix channel.

You can download libssh-0.12.1 here and libssh-0.11.5 in here.
ChangeLog for libssh 0.12.1:
Security:

https://github.com/advisories/GHSA-6j7f-8jjp-mm8c: Stack buffer overflow in SFTP server longname construction
https://github.com/advisories/GHSA-x94w-cg8g-g593: Information disclosure via short GSSAPI Curve25519 public key
https://github.com/advisories/GHSA-4846-7xwg-pw5m: Denial of service via zero advertised channel packet size (accidentally excluded from this release, see 0.12.2)
https://github.com/advisories/GHSA-qp28-hpg5-j7xc: Denial of service via oversized SFTP read length
https://github.com/advisories/GHSA-97fp-2vw9-q5jg: Denial of service via unchecked ProxyCommand fork() failure
https://github.com/advisories/GHSA-fvwj-j79q-57v7: Information disclosure via ProxyCommand %r username expansion
https://github.com/advisories/GHSA-mq2j-7vq4-77m8: Integrity downgrade via OpenSSL AES-GCM tag verification
https://github.com/advisories/GHSA-4h4r-q9xg-gfmm: Denial of service via SFTP responses with unknown request IDs
https://github.com/advisories/GHSA-jp6g-7mqj-wj53: Denial of service via automatic certificate authentication loop
https://github.com/advisories/GHSA-cr6p-6527-344m: Use-after-free via data callbacks on closed channels
https://github.com/advisories/GHSA-x5cr-v39m-53gw: Authentication bypass via missing GSSAPI principal check
Zero-initialize every ssh_string

Compatibility:

Fix compatibility with C23 / gcc16
Allow hybrid ML-KEM key exchange in FIPS mode

Bugfixes:

Fix multiple memory leaks, null checks, and error checks
Fix parameter size mismatch in mlkem768x25519-sha256
Fix client SFTP messages being ignored if sent at high rate
Validate peer public key in DH key exchange
Fix ambiguous error reporting of sftp_init
Fix hidden integer underflow in socket packet callback
Avoid remote window overflow
Fix socket data callback return value on rekey failure
Avoid off-by-one overflow during kbdint authentication
Avoid logging uninitialized sequence numbers
Avoid double conversion of SFTP version number
Send correct SFTP server version number
Avoid handling repeated SFTP INIT messages
Harmonize return values from SFTP server callbacks