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CVE

CVE-2026-34483

Apache Tomcat has an Improper Encoding or Escaping of Output vulnerability in the JsonAccessLogValve
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CVE

CVE-2026-34483

Apache Tomcat has an Improper Encoding or Escaping of Output vulnerability in the JsonAccessLogValve

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.

Package Versions Affected

Package Version
patch Availability
No items found.

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CVSS Version

Severity
Base Score
CVSS Version
Score Vector
C
H
U
7.5
-
3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
C
H
U
0
-
3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
C
H
U
7.5
-
3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Related Resources

No items found.

References

https://nvd.nist.gov/vuln/detail/CVE-2026-34483, https://github.com/apache/tomcat, https://lists.apache.org/thread/j1w7304yonlr8vo1tkb5nfs7od1y228b, http://www.openwall.com/lists/oss-security/2026/04/09/26

Severity

7.5

CVSS Score
0
10

Basic Information

Ecosystem
Base CVSS
7.5
EPSS Probability
0.00067%
EPSS Percentile
0.20924%
Introduced Version
9.0.40,11.0.12,10.1.47,11.0.0-M1,10.0.0-M1,8.0.1,8.0.0-RC1,7.0.0,6.0.13,7.0.35,0
Fix Available
9.0.116,11.0.21,10.1.54,9.0.117,8.8.22-r0,8.6.39-r0,8.7.27-r0,2025.0.8-r11,2025.1.6-r9,2025.2.4-r5,2025.4.3-r6,2026.0.2-r6,2025.0.8-r13,2025.1.6-r10,2025.2.4-r6,2025.4.3-r7,2026.0.2-r7,3.2.0-r6,3.2.0-r2,5.5.0-r8,5.5.0-r4,4.3.1.1-r11

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