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CVE-2026-42498 (GCVE-0-2026-42498)

Vulnerability from cvelistv5 – Published: 2026-05-12 15:17 – Updated: 2026-05-13 15:59
VLAI
Title
Apache Tomcat: WebSocket authentication header exposure
Summary
Exposure of HTTP Authentication Header to unexpected hosts during WebSocket authentication vulnerability in Apache Tomcat. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.21, from 10.1.0-M1 through 10.1.54, from 9.0.2 through 9.0.117, from 8.5.24 through 8.5.100, from 7.0.83 through 7.0.109. Users are recommended to upgrade to version 11.0.22, 10.1.55 or 9.0.118, which fix the issue.
Severity
7.3 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-13 15:58 UTC
CWE
  • CWE-200 - Exposure of HTTP Authentication Header to unexpected hosts
Assigner
References
Impacted products
Vendor Product Version CPE status
Apache Software Foundation Apache Tomcat Affected: 11.0.0-M1 , ≤ 11.0.21 (semver)
Affected: 10.1.0-M1 , ≤ 10.1.54 (semver)
Affected: 9.0.2 , ≤ 9.0.117 (semver)
Affected: 8.5.24 , ≤ 8.5.100 (semver)
Affected: 7.0.83 , ≤ 7.0.109 (semver)
guessed Create a notification for this product.
Credits
lokerxx
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • 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.
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  • 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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