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TI-2026-25916 Aliases CVE-2026-33523GHSA-fc75-39v4-qm5p

Apache HTTP Server: multiple modules: HTTP response splitting forwarding malicious status line

Priority LOW 35CWE-443Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
Low · Low · None
Fix status
Partial Red Hat: 3 fixed, 5 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat.

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00436 38th percentileScored 2026-11-07
Fix Partial Red Hat: 3 advisoriesRed Hat: 3 fixed, 5 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ApacheApache HTTP Server2.4.0 – 2.4.66—No fix listedCNA
  • Apache HTTP Server VendorApache Affected 2.4.0 – 2.4.66 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*2.4.0 to before 2.4.67VulnerableApache
  • cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:* Versions 2.4.0 to before 2.4.67 Vulnerable ·Apache

Remediation

Red Hat 3 advisories

  • RHSA-2026:73076 Released 2026-09-29 · Red Hat rating Moderate
    Red Hat JBoss Core Services Apache HTTP Server 2.4.62 SP6 security update
    • Red Hat JBoss Core Services on RHEL 8 jbcs-httpd24-httpd-2.4.62-17.el8jbcs, jbcs-httpd24-httpd-devel-2.4.62-17.el8jbcs, jbcs-httpd24-httpd-manual-2.4.62-17.el8jbcs +12
  • RHSA-2026:73077 Released 2026-09-29 · Red Hat rating Moderate
    Red Hat JBoss Core Services Apache HTTP Server 2.4.62 SP6 security update
    • Red Hat JBoss Core Services 2.4.62.SP6
  • RHSA-2026:17080 Released 2026-05-13 · Red Hat rating Moderate
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images httpd-2.4.67-1.hum1@aarch64, httpd-2.4.67-1.hum1@src, httpd-2.4.67-1.hum1@x86_64 +10

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 6AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 7AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat Hardened ImagesFixed RHSA-2026:17080
Red Hat JBoss Core Services 2.4.62.SP6Fixed RHSA-2026:73077
Red Hat JBoss Core Services on RHEL 8Fixed RHSA-2026:73076
Not affected: 1 product
  • Red Hat Hardened Images

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-33523
  2. 2026-10-03 Alias added: GHSA-fc75-39v4-qm5p
  3. 2026-11-06 Affected versions changed · Red Hat

References

Advisory 2

  • TI-2021-18535 Path Traversal and Remote Code Execution in Apache HTTP Server 2.4.49 and 2.4.50 (incomplete fix of CVE-2021-41773) KEVCVSS 3.1CRITICAL 9.8
  • TI-2021-18417 Path traversal and file disclosure vulnerability in Apache HTTP Server 2.4.49 KEVCVSS 3.1CRITICAL 9.8
  • TI-2024-25716 Apache HTTP Server weakness in mod_rewrite when first segment of substitution matches filesystem path. KEVCVSS 3.1CRITICAL 9.1
  • TI-2021-17490 mod_proxy SSRF KEVCVSS 3.1CRITICAL 9.0
  • TI-2019-00184 Use after free in Apache HTTP Server KEVCVSS 3.1HIGH 7.8
  • TI-2009-03392 The TLS protocol, and the SSL protocol 3.0 and possibly earlier, as used in Microsoft… CVSS 3.1CRITICAL 9.8
See all 349 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences