Vulnerability-Lookup

GHSA-RV64-5GF8-9QQ8

Vulnerability from github – Published: 2026-04-09 21:31 – Updated: 2026-04-10 21:38

Summary

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

Details

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.

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Show details on source website

JSON

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{
  "affected": [
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.apache.tomcat:tomcat-catalina"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "9.0.40"
            },
            {
              "fixed": "9.0.116"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.apache.tomcat:tomcat-catalina"
      },
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        {
          "events": [
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              "introduced": "10.1.0-M1"
            },
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              "fixed": "10.1.54"
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          "type": "ECOSYSTEM"
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    },
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        "name": "org.apache.tomcat:tomcat-catalina"
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              "introduced": "11.0.0-M1"
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              "fixed": "11.0.21"
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      "package": {
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        "name": "org.apache.tomcat.embed:tomcat-embed-core"
      },
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        {
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              "introduced": "11.0.0-M1"
            },
            {
              "fixed": "11.0.21"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-34483"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-116"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-10T21:38:21Z",
    "nvd_published_at": "2026-04-09T20:16:24Z",
    "severity": "HIGH"
  },
  "details": "Improper Encoding or Escaping of Output vulnerability in the JsonAccessLogValve component of Apache Tomcat.\n\nThis 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.\n\nUsers are recommended to upgrade to version 11.0.21, 10.1.54 or 9.0.117 , which fix the issue.",
  "id": "GHSA-rv64-5gf8-9qq8",
  "modified": "2026-04-10T21:38:22Z",
  "published": "2026-04-09T21:31:30Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34483"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/apache/tomcat"
    },
    {
      "type": "WEB",
      "url": "https://lists.apache.org/thread/j1w7304yonlr8vo1tkb5nfs7od1y228b"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2026/04/09/26"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Apache Tomcat has an Improper Encoding or Escaping of Output vulnerability in the JsonAccessLogValve"
}

CVE-2026-34483 (GCVE-0-2026-34483)

Vulnerability from cvelistv5 – Published: 2026-04-09 19:30 – Updated: 2026-04-10 20:17

Title

Apache Tomcat: Incomplete escaping of JSON access logs

Summary

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.

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-10 20:16 UTC

CWE

CWE-116 - Improper Encoding or Escaping of Output

Assigner

apache CNA under the mitre root

CNA scorecard B 76/100 over 1024 records in the last 180 days details

References

2 references

URL	Tags
https://lists.apache.org/thread/j1w7304yonlr8vo1t…	vendor-advisory
http://www.openwall.com/lists/oss-security/2026/0…

Impacted products

1 product

Vendor	Product	Version
Apache Software Foundation	Apache Tomcat	Affected: 11.0.0-M1 , ≤ 11.0.20 (semver) Affected: 10.1.0-M1 , ≤ 10.1.53 (semver) Affected: 9.0.40 , ≤ 9.0.116 (semver) Affected: 8.5.84 , ≤ 8.5.100 (semver) Unaffected: 0 , ≤ 8.5.83 (semver)

Credits

Bartlomiej Dmitruk, striga.ai

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

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Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

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