Low 3.1Published Sep 9, 2025

CVE-2025-8277Libssh: memory exhaustion via repeated key exchange in libssh

Updated under an hour ago (Oct 26, 2026, 2:30 PM ET)

This data is behind schedule: last updated Oct 26, 2026, 2:30 PM ET. We are working on it.Behind: CVE records (cvelistV5).

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It affects Red Hat Enterprise Linux 9 and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Red Hat Enterprise Linux 9

Exploited in the last 30 days

A flaw was found in libssh's handling of key exchange (KEX) processes when a client repeatedly sends incorrect KEX guesses. The library fails to free memory during these rekey operations, which can gradually exhaust system memory. This issue can lead to crashes on the client side, particularly when using libgcrypt, which impacts application stability and availability.

CVSS: 3.1 LOW (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
Weakness (CWE): CWE-401
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: redhat
NVD analysis: Deferred
Record last updated: Sep 1, 2026
First seen by InfoSec Signals: Oct 18, 2026

Affected products

Affected products

Red Hat Red Hat Enterprise Linux 9 redhat:enterprise_linux	from 0:0.10.4-18.el9 not affected	CNA record
Red Hat Red Hat OpenShift Container Platform 4 redhat:openshift	4	CNA record

References

References

https://access.redhat.com/errata/RHSA-2026:18683	vendor-advisory, x-refsource-redhat
https://access.redhat.com/security/cve/CVE-2025-8277	vdb-entry, x-refsource-redhat
https://bugzilla.redhat.com/show_bug.cgi?id=2383888	issue-tracking, x-refsource-redhat
https://www.libssh.org/security/advisories/CVE-2025-8277.txt

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.