CVE-2026-33523 (GCVE-0-2026-33523)

Vulnerability from cvelistv5 – Published: 2026-05-04 14:40 – Updated: 2026-05-04 17:32
VLAI
Title
Apache HTTP Server: multiple modules: HTTP response splitting forwarding malicious status line
Summary
HTTP response splitting vulnerability in multiple Apache HTTP Server modules with untrusted or compromised backend servers. This issue affects Apache HTTP Server: from through 2.4.66. Users are recommended to upgrade to version 2.4.67, which fixes the issue.
Severity
No CVSS data available.
CWE
  • CWE-443 - HTTP response splitting
Assigner
References
Impacted products
Vendor Product Version
Apache Software Foundation Apache HTTP Server Affected: 2.4.0 , ≤ 2.4.66 (semver)
Create a notification for this product.
Credits
Haruki Oyama (Waseda University) Merih Mengisteab Dawit Jeong
Show details on NVD website
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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.

Sightings

Author Source Type Date Other

Nomenclature

  • 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.
  • 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.



Detection rules are retrieved from Rulezet.