CVE-2026-56854CWE-863broken-access-control

CVE-2026-56854

High · published August 28, 2026

CVSS v3.1
7.5
EPSS
0%
Percentile
37.0
In the wild
Unconfirmed
What it is

The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.00437 · 37.0th percentile
Weakness
CWE-863 · Incorrect Authorization
Published
2026-08-28T20:18Z
References (3)
EPSS history
Timeline
  • 30 AUG 16:18Z
    EPSS moved — → 0%
    epss
  • 28 AUG 15:14Z
    Source-address critical option not enforced for non-public-key auth callbacks in golang.org/x/crypto/ssh
    cvelistv5