CVE-2025-8277

EUVD-2025-27246
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
3.1 LOW
NETWORK
HIGH
LOW
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: 21%
Debian logo
Debian Releases
Debian Product
Codename
libssh
bookworm
0.10.6-0+deb12u2
fixed
bookworm (security)
vulnerable
bullseye
vulnerable
bullseye (security)
0.9.8-0+deb11u2
fixed
forky
0.12.0-3
fixed
sid
0.12.0-3
fixed
trixie
0.11.2-1+deb13u1
fixed
openSUSE logo
openSUSE / SLES Releases
openSUSE Product
Release
libssh-config
suse enterprise desktop 15 SP6
0.9.8-150600.11.6.1
fixed
suse enterprise desktop 15 SP7
0.9.8-150600.11.6.1
fixed
suse enterprise sap 15 SP6
0.9.8-150600.11.6.1
fixed
suse enterprise sap 15 SP7
0.9.8-150600.11.6.1
fixed
suse enterprise server 15 SP4
0.9.8-150400.3.12.1
fixed
suse enterprise server 15 SP6
0.9.8-150600.11.6.1
fixed
suse enterprise server 15 SP7
0.9.8-150600.11.6.1
fixed
libssh-devel
suse enterprise desktop 15 SP6
0.9.8-150600.11.6.1
fixed
suse enterprise desktop 15 SP7
0.9.8-150600.11.6.1
fixed
suse enterprise sap 15 SP6
0.9.8-150600.11.6.1
fixed
suse enterprise sap 15 SP7
0.9.8-150600.11.6.1
fixed
suse enterprise server 15 SP4
0.9.8-150400.3.12.1
fixed
suse enterprise server 15 SP6
0.9.8-150600.11.6.1
fixed
suse enterprise server 15 SP7
0.9.8-150600.11.6.1
fixed
libssh4
suse enterprise desktop 15 SP6
0.9.8-150600.11.6.1
fixed
suse enterprise desktop 15 SP7
0.9.8-150600.11.6.1
fixed
suse enterprise sap 15 SP6
0.9.8-150600.11.6.1
fixed
suse enterprise sap 15 SP7
0.9.8-150600.11.6.1
fixed
suse enterprise server 15 SP4
0.9.8-150400.3.12.1
fixed
suse enterprise server 15 SP6
0.9.8-150600.11.6.1
fixed
suse enterprise server 15 SP7
0.9.8-150600.11.6.1
fixed
libssh4-32bit
suse enterprise desktop 15 SP6
0.9.8-150600.11.6.1
fixed
suse enterprise desktop 15 SP7
0.9.8-150600.11.6.1
fixed
suse enterprise sap 15 SP6
0.9.8-150600.11.6.1
fixed
suse enterprise sap 15 SP7
0.9.8-150600.11.6.1
fixed
suse enterprise server 15 SP4
0.9.8-150400.3.12.1
fixed
suse enterprise server 15 SP6
0.9.8-150600.11.6.1
fixed
suse enterprise server 15 SP7
0.9.8-150600.11.6.1
fixed
Red Hat logo
Red Hat Enterprise Linux Releases
Red Hat Product
Release
libssh
RHEL 9
0:0.10.4-18.el9
fixed
libssh-config
RHEL 9
0:0.10.4-18.el9
fixed
libssh-devel
RHEL 9
0:0.10.4-18.el9
fixed
Common Weakness Enumeration
References
https://access.redhat.com/errata/RHSA-2026:18683
https://access.redhat.com/security/cve/CVE-2025-8277
https://bugzilla.redhat.com/show_bug.cgi?id=2383888
https://www.libssh.org/security/advisories/CVE-2025-8277.txt