Status: UPDATED | Advisory ID: CVE-2026-34483
| CVE | CVE-2026-34483 |
| CVSS Score / Version | 7.5 (High) / CVSS v3.1 |
| Updated | 2026-09-24 |
| CVSS Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| CVSS Prose | attack vector is network; attack complexity is low; privileges required is none; user interaction is none; scope is unchanged; confidentiality impact is high; integrity impact is none; availability impact is none. |
| Affected products | Apache Tomcat |
| Classified as | CWE-116 (Improper Encoding or Escaping of Output) |
| Exploitation prediction (EPSS) | 0.62% probability of exploitation in the next 30 days (48% percentile) -- FIRST.org's EPSS model. |
| Vendor | Product | Affected Versions | Patch Status |
|---|---|---|---|
| Apache | Tomcat |
| Subsystems | General OT |
| Sectors | Multiple |
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.
Monitor Apache's web page for any future patch releases. See vendor advisory link below.
| Source | Reference |
|---|---|
| NVD | https://nvd.nist.gov/vuln/detail/CVE-2026-34483 |
| CVE | https://www.cve.org/CVERecord?id=CVE-2026-34483 |
| Vendor advisory | https://lists.apache.org/thread/j1w7304yonlr8vo1tkb5nfs7od1y228b |