7.5

CVE-2026-34483: apache software foundation apache tomcat Improper Encoding or Escaping of Output

CVSS: 7.5v3.1HighAnalyzed
AliasesUBUNTU-CVE-2026-34483DEBIAN-CVE-2026-34483CGA-5hm6-j8mw-r88h
Published 09-04-2026Last modified 10-04-2026
Open JSON

Vulnerability summary

CVE-2026-34483 is a high (CVSS 7.5) Improper Encoding or Escaping of Output vulnerability in apache software foundation apache tomcat. EPSS estimates a 0.46% chance of exploitation in the next 30 days, higher than 38.5% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.46%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 19 · Related 11
MGASA-2026-0095OPENSUSE-SU-2026:10547-1OPENSUSE-SU-2026:10548-1OPENSUSE-SU-2026:10549-1OPENSUSE-SU-2026:20595-1OPENSUSE-SU-2026:20611-1

Timeline

  1. 09-04-2026
    PublishedVulnerability first disclosed.
  2. 10-04-2026
    Last modifiedVulnerability information updated.

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 metrics

7 scores · 7 sources · 1 version

EPSS trend

Probability

0.46%

Chance of exploitation in the next 30 days

Percentile

39%

Versus all other CVEs

30-day change

0.00 pp

From 0.46% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.46%

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

Chainguard20 products
  • camunda-8.8< 8.8.22-r0
  • camunda-zeebe-8.6< 8.6.39-r0
  • camunda-zeebe-8.7< 8.7.27-r0
  • camunda-zeebe-8.8< 8.8.22-r0
  • kayenta-2025.0< 2025.0.8-r11
Debian3 products
  • tomcat10< 10.1.55-1~deb12u1 | < 10.1.55-1~deb13u1 | < 10.1.54-1
  • tomcat11< 11.0.22-1~deb13u1 | < 11.0.21-1
  • tomcat9< 9.0.70-2
Ubuntu3 products
  • tomcat10All versions (No fix recorded)
  • tomcat11All versions (No fix recorded)
  • tomcat9All versions (No fix recorded)
Org.apache.tomcat2 products
  • tomcat≥ 9.0.40, < 9.0.116 | ≥ 10.1.0-M1, < 10.1.54 | ≥ 11.0.0-M1, < 11.0.21
  • tomcat-catalina≥ 9.0.40, < 9.0.116 | ≥ 10.1.0-M1, < 10.1.54 | ≥ 11.0.0-M1, < 11.0.21
Wolfi2 products
  • thingsboard-tb-mqtt-transport< 4.3.1.1-r11
  • thingsboard-tb-node< 4.3.1.1-r11
Apache1 product
  • tomcat≥ 9.0.40, < 9.0.117 | ≥ 10.1.0, < 10.1.54 | ≥ 11.0.0, < 11.0.21
Apache software foundation1 product
  • apache tomcat≥ 11.0.0-M1, ≤ 11.0.20 | ≥ 10.1.0-M1, ≤ 10.1.53 | ≥ 9.0.40, ≤ 9.0.116 | ≥ 8.5.84, ≤ 8.5.100
Org.apache.tomcat.embed1 product
  • tomcat-embed-core≥ 9.0.40, < 9.0.116 | ≥ 10.1.0-M1, < 10.1.54 | ≥ 11.0.0-M1, < 11.0.21

8 vendors · 33 products

References

8 links