7.5

CVE-2026-13046: watchguard fireware Deserialization of Untrusted Data

CVSS: 7.5v4.0HighAnalyzed
Published 29-09-2026Last modified 01-10-2026
Open JSON

Vulnerability summary

CVE-2026-13046 is a high (CVSS 7.5) Deserialization of Untrusted Data vulnerability in watchguard fireware. EPSS estimates a 0.37% chance of exploitation in the next 30 days, higher than 29.6% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v4.0 (CVE.org)
EPSS score
0.37%
0%100%
Low · Change unavailable
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 29-09-2026
    PublishedVulnerability first disclosed.
  2. 01-10-2026
    Last modifiedVulnerability information updated.

Description

A deserialization of untrusted data vulnerability in WatchGuard Fireware OS's SAML single sign-on session handling (samld) allows an attacker who has already obtained the ability to write files on the appliance to execute arbitrary code in the context of the samld service by causing samld to load a maliciously crafted session file.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

0.37%

Chance of exploitation in the next 30 days

Percentile

30%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

30-09-202621-10-2026
EPSS score
0.37%

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

Watchguard2 products
  • fireware≥ 12.0, < 12.11.10 | ≥ 12.12, < 12.12.3 | ≥ 2025.0, < 2026.2.3 | ≥ 2026.3, < 2026.3.2
  • fireware os≥ 2026.3, < 2026.3.2 | ≥ 2025.0, < 2026.2.3 | ≥ 12.0, < 12.12.3 | ≥ 12.11, < 12.11.10

1 vendor · 2 products

References

1 links