CVE-2023-6918
Libssh: missing checks for return values for digests
A flaw was found in the libssh implements abstract layer for message digest (MD) operations implemented by different supported crypto backends. The return values from these were not properly checked, which could cause low-memory situations failures, NULL dereferences, crashes, or usage of the uninitialized memory as an input for the KDF. In this case, non-matching keys will result in decryption/integrity failures, terminating the connection.
Fixes and workarounds
Workaround
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Source: CNA: redhatAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| Red Hat Enterprise Linux 8 Red Hat libssh
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:0.9.6-14.el8; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 9 Red Hat libssh
https://access.redhat.com/downloads/content/package-browser/ |
≥ 0:0.10.4-13.el9; < * (unaffected, rpm)
Other versions: affected |
CNA: redhat |
| Red Hat Enterprise Linux 6 Red Hat libssh2
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: unknown |
CNA: redhat |
| Red Hat Enterprise Linux 7 Red Hat libssh
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: unknown |
CNA: redhat |
| Red Hat Enterprise Linux 7 Red Hat libssh2
https://access.redhat.com/downloads/content/package-browser/ |
Range not reported
Other versions: unknown |
CNA: redhat |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 3.7 low |
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L | CNA: redhat |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://access.redhat.com/errata/RHSA-2024:2504CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/errata/RHSA-2024:3233CNA: redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2023-6918CNA: redhat · vdb-entry, x_refsource_REDHAT
- https://bugzilla.redhat.com/show_bug.cgi?id=2254997CNA: redhat · issue-tracking, x_refsource_REDHAT
- https://www.libssh.org/2023/12/18/libssh-0-10-6-and-libssh-0-9-8-security-releases/CNA: redhat
- https://www.libssh.org/security/advisories/CVE-2023-6918.txtCNA: redhat
- https://access.redhat.com/errata/RHSA-2024:2504ADP: CVE · vendor-advisory, x_refsource_REDHAT, x_transferred
- https://access.redhat.com/errata/RHSA-2024:3233ADP: CVE · vendor-advisory, x_refsource_REDHAT, x_transferred
- https://access.redhat.com/security/cve/CVE-2023-6918ADP: CVE · vdb-entry, x_refsource_REDHAT, x_transferred
- https://bugzilla.redhat.com/show_bug.cgi?id=2254997ADP: CVE · issue-tracking, x_refsource_REDHAT, x_transferred
- https://lists.fedoraproject.org/archives/list/[email protected]/message/LZQVUHWVWRH73YBXUQJOD6CKHDQBU3DM/ADP: CVE · x_transferred
- https://lists.fedoraproject.org/archives/list/[email protected]/message/MKQRBF3DWMWPH36LBCOBUTSIZRTPEZXB/ADP: CVE · x_transferred
- https://www.libssh.org/2023/12/18/libssh-0-10-6-and-libssh-0-9-8-security-releases/ADP: CVE · x_transferred
- https://www.libssh.org/security/advisories/CVE-2023-6918.txtADP: CVE · x_transferred
- https://security.netapp.com/advisory/ntap-20250214-0009/ADP: CVE
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