7.5

CVE-2026-56854: Source-address critical option not enforced for non-public-key auth callbacks in golang.org/x/crypto/ssh

Awaiting analysis
AliasesUBUNTU-CVE-2026-56854DEBIAN-CVE-2026-56854CGA-226p-7ffp-v7f6
Published 28-08-2026Last modified 28-08-2026

Vulnerability summary

CVE-2026-56854 is a high (CVSS 7.5) Incorrect Authorization vulnerability in golang.org/x/crypto golang.org/x/crypto/ssh. EPSS estimates a 0.44% chance of exploitation in the next 30 days, higher than 38% of scored vulnerabilities.

Priority
Prioritisesevere

Severe, CVSS 7.5 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 0% (FIRST, 03-11-2026)

Source freshness unavailable

How is this decided?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.44%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 54 · Related 55
OPENSUSE-SU-2026:11699-1OPENSUSE-SU-2026:11727-1OPENSUSE-SU-2026:11731-1OPENSUSE-SU-2026:11732-1OPENSUSE-SU-2026:11752-1OPENSUSE-SU-2026:11803-1

Timeline

  1. 28-08-2026
    PublishedVulnerability first disclosed.
  2. 28-08-2026
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.44%

Chance of exploitation in the next 30 days

Percentile

38%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.44% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Chainguard200 products
  • aactl< 0.4.12-r73
  • acm-controllerAll versions (No fix recorded)
  • acm-controller-fipsAll versions (No fix recorded)
  • actAll versions (No fix recorded)
  • actions-runner-controllerAll versions (No fix recorded)

1 vendor · 200 products · Showing 200 of 3538

References

8 links