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    CVE-2012-4559

    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.

    Published:Nov 30, 2012
    Last Modified:Apr 11, 2025
    EPS:Nov 30, 2012
    EPSS Score:0.03818
    CVSS Score:6.8

    Affected Products

    Vendor
    Libssh
    Product
    Libssh

    Exploits

    No exploit reference

    Common Weakness Enumeration

    No CWE recorded yet

    Common Attack Pattern Enumeration and Classification (CAPEC)

    No CAPEC recorded yet

    Related CVEs

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    CVE-2026-59849 (CVSS 3.1) — A flaw was found in libssh. Logic errors in automatic certificate-based public key authentication can cause li…
    CVE-2026-59848 (CVSS 5.3) — A flaw was found in libssh. A malicious SFTP server can send responses for unknown request IDs that libssh cli…
    CVE-2026-59847 (CVSS 5.9) — A flaw was found in libssh. Incorrect AES-GCM finalization checks in builds using the OpenSSL backend can effe…
    CVE-2026-59846 (CVSS 3.9) — A flaw was found in libssh. A malicious username expanded through %r in ProxyCommand handling can inject shell…
    CVE-2026-59845 (CVSS 5.3) — A flaw was found in libssh. When ProxyCommand is used, an unchecked fork() failure can be stored as process ID…
    CVE-2026-59844 (CVSS 6.5) — A flaw was found in libssh. A remote authenticated client can issue SSH_FXP_READ requests with an arbitrarily …
    CVE-2026-59843 (CVSS 6.5) — A flaw was found in libssh. A remote authenticated peer can advertise a zero maximum packet size in SSH_MSG_CH…
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    References

    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/
    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/
    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

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High