CVE-2012-4559

medium
Published 2012-11-30 · Modified 2026-04-29
CVSS v3
CVSS v2
6.8
VIR risk
6.8

Description

Multiple double free vulnerabilities in the (1) agent_sign_data function in agent.c, (2) channel_request function in channels.c, (3) ssh_userauth_pubkey function in auth.c, (4) sftp_parse_attr_3 function in sftp.c, and (5) try_publickey_from_file function in keyfiles.c in libssh before 0.5.3 allow remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via unspecified vectors.

Predictions

Exploit likelihood
20%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2012-4559

vendor Authored 2026-05-27

Vendor advisory: secalert@redhat.com — http://www.libssh.org/2012/11/20/libssh-0-5-3-security-release/

OS impact

OSVersionStatusFixed in
debian debianbookwormfixed0.5.3-1
debian debianbullseyefixed0.5.3-1
debian debianforkyfixed0.5.3-1
debian debiansidfixed0.5.3-1
debian debiantrixiefixed0.5.3-1

Application impact

VendorProductVersionsFixed
libsshlibssh{"endIncluding":"0.5.2"}
libsshlibssh0.4.7
libsshlibssh0.4.8
libsshlibssh0.5.0
libsshlibssh0.5.1

References

CWEs

CWE-399

Verify integrity in audit chain (admin only). AS-IS.