6.9

CVE-2026-40435: f5 big-ip Unprotected Alternate Channel

CVSS: 6.9v4.0MediumAnalyzed
Published 13-05-2026Last modified 13-05-2026
Open JSON

Vulnerability summary

CVE-2026-40435 is a medium (CVSS 6.9) Unprotected Alternate Channel vulnerability in f5 big-ip. EPSS estimates a 0.31% chance of exploitation in the next 30 days, higher than 22.8% of scored vulnerabilities.

Overall risk
28/100
0100
Medium · default modelHow is this calculated?
CVSS score
6.9/10
010
Medium · v4.0 (CVE.org)
EPSS score
0.31%
0%100%
Low · +0.09 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 13-05-2026
    PublishedVulnerability first disclosed.
  2. 13-05-2026
    Last modifiedVulnerability information updated.

Description

When configured, IP-based access restrictions for httpd do not cover all endpoints, which may allow connections from blocked addresses.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

CVSS metrics

4 scores · 2 sources · 2 versions

EPSS trend

Probability

0.31%

Chance of exploitation in the next 30 days

Percentile

23%

Versus all other CVEs

30-day change

+0.09 pp

From 0.23% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.31%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

F522 products

1 vendor · 22 products

References

1 links