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Vulnerability record · CVE-2012-4559 · published 30 November 2012

CVE-2012-4559: Libssh vulnerability

Libssh · Libssh

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.

6.8 CVSS 2.0 Medium EPSS 5.2% · top 7.8% CWE-399 · CWE-399
6.8CVSS 2.0 base score
5.2%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
26References
16 Jun 2026Last modified by NVD

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.

AV:N/AC:M/Au:N/C:P/I:P/A:P

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
http://lists.fedoraproject.org/pipermail/package-announce/2012-November/093313.html
http://lists.fedoraproject.org/pipermail/package-announce/2012-November/093474.html
http://lists.opensuse.org/opensuse-security-announce/2012-12/msg00002.html
http://lists.opensuse.org/opensuse-updates/2012-12/msg00016.html
http://lists.opensuse.org/opensuse-updates/2013-01/msg00021.html
http://www.debian.org/security/2012/dsa-2577
http://www.libssh.org/2012/11/20/libssh-0-5-3-security-release/ Vendor Advisory
http://www.mandriva.com/security/advisories?name=MDVSA-2012:175
http://www.openwall.com/lists/oss-security/2012/11/20/3
http://www.securityfocus.com/bid/56604
http://www.ubuntu.com/usn/USN-1640-1
https://bugzilla.redhat.com/show_bug.cgi?id=871612
https://exchange.xforce.ibmcloud.com/vulnerabilities/80218
http://lists.fedoraproject.org/pipermail/package-announce/2012-November/093313.html
http://lists.fedoraproject.org/pipermail/package-announce/2012-November/093474.html
http://lists.opensuse.org/opensuse-security-announce/2012-12/msg00002.html
http://lists.opensuse.org/opensuse-updates/2012-12/msg00016.html
http://lists.opensuse.org/opensuse-updates/2013-01/msg00021.html
http://www.debian.org/security/2012/dsa-2577
http://www.libssh.org/2012/11/20/libssh-0-5-3-security-release/ Vendor Advisory
http://www.mandriva.com/security/advisories?name=MDVSA-2012:175
http://www.openwall.com/lists/oss-security/2012/11/20/3
http://www.securityfocus.com/bid/56604
http://www.ubuntu.com/usn/USN-1640-1
https://bugzilla.redhat.com/show_bug.cgi?id=871612
https://exchange.xforce.ibmcloud.com/vulnerabilities/80218

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Source: NIST National Vulnerability Database (record CVE-2012-4559), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.