CVE-2015-3146
CVE-2015-3146 is a high-severity vulnerability in Libssh with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 4% (89th percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: Libssh
- Published:
- Last modified:
Description
The (1) SSH_MSG_NEWKEYS and (2) SSH_MSG_KEXDH_REPLY packet handlers in package_cb.c in libssh before 0.6.5 do not properly validate state, which allows remote attackers to cause a denial of service (NULL pointer dereference and crash) via a crafted SSH packet.
Frequently asked questions
- What is CVE-2015-3146?
- The (1) SSH_MSG_NEWKEYS and (2) SSH_MSG_KEXDH_REPLY packet handlers in package_cb.c in libssh before 0.6.5 do not properly validate state, which allows remote attackers to cause a denial of service (NULL pointer dereference and crash) via a crafted SSH packet.
- How severe is CVE-2015-3146?
- CVE-2015-3146 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2015-3146 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2015-3146?
- CVE-2015-3146 primarily affects Libssh. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2015-3146?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2015-3146 published?
- CVE-2015-3146 was published on 2016-04-13 and last updated on 2026-06-17.
References
- http://lists.fedoraproject.org/pipermail/package-announce/2015-July/161802.html
- http://lists.fedoraproject.org/pipermail/package-announce/2015-May/158013.html
- http://www.debian.org/security/2016/dsa-3488
- http://www.ubuntu.com/usn/USN-2912-1
- https://git.libssh.org/projects/libssh.git/commit/?h=libssh-0.6.5&id=94f6955fbaee6fda9385a23e505497efe21f5b4f
- https://www.libssh.org/2015/04/30/libssh-0-6-5-security-and-bugfix-release/
- https://www.libssh.org/security/advisories/CVE-2015-3146.txt
Affected products (8)
- cpe:2.3:a:libssh:libssh:*:*:*:*:*:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:lts:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
- cpe:2.3:o:canonical:ubuntu_linux:15.10:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:7.0:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:21:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:22:*:*:*:*:*:*:*
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