authentication bypass via missing GSSAPI principal check
Summary
A flaw was found in libssh. On servers with GSSAPIKeyExchange enabled, the gssapi-keyex path does not verify whether the authenticated Kerberos principal is authorized for the requested local user, allowing authenticated clients to log in as arbitrary users. Red Hat severity: Important — CVSS 8.8 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H). Weakness: CWE-863. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Hardened Images. Red Hat lists Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9 as not affected. Red Hat does not currently list a fixing RHSA for this CVE.
What this means
In plain English
A flaw was found in libssh. On servers with GSSAPIKeyExchange enabled, the gssapi-keyex path does not verify whether the authenticated Kerberos principal is authorized for the requested local user, allowing authenticated clients to log in as arbitrary users. Red Hat severity: Important — CVSS 8.8 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H). Weakness: CWE-863. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Hardened Images. Red Hat lists Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9 as not affected. Red Hat does not currently list a fixing RHSA for this CVE. The official description requires local access to the affected system. An authentication bypass can allow protected functionality to be reached without completing the intended identity checks.
Recommended action
Vendor mitigation: Disable GSSAPIKeyExchange. No fixed release is recorded in the parsed advisory, so treat these controls as temporary until the vendor confirms a patched release.
Rewritten locally from the scraped official advisory data above; no generative API is used. The vendor advisory is authoritative.
Affected versions
No affected-version range was extracted from the source record. The vendor advisory is authoritative — check it before change work.
Official advisory · high-confidence parse· fetched 3 hours ago·verify at source
Fixed versions
No fixed release is recorded yet. That does not prove no patch exists — confirm against the vendor advisory.
Official advisory · high-confidence parse· fetched 3 hours ago·verify at source
Mitigation checklist
- Disable GSSAPIKeyExchange.
Official advisory · high-confidence parse· fetched 3 hours ago·verify at source
Discussion(0)
No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.
Sign in to join the discussion.