SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-34483

Improper Encoding or Escaping of Output vulnerability in the JsonAccessLogValve component of Apache Tomcat.

HIGH 7.5EPSS 0.46%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.46%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Improper Encoding or Escaping of Output vulnerability in the JsonAccessLogValve component of Apache Tomcat. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.20, from 10.1.0-M1 through 10.1.53, from 9.0.40 through 9.0.116. Users are recommended to upgrade to version 11.0.21, 10.1.54 or 9.0.117 , which fix the issue.

CVSS 3.1
7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS
0.46% probability · 39th percentile
CISA KEV
Not listed
Weakness
CWE-116
Affected
apache/tomcat
Source
security@apache.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.