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TI-2026-26223 Aliases CVE-2026-33857GHSA-v5qg-p44g-5728

Apache HTTP Server: Off-by-one OOB reads in AJP getter functions

Priority LOW 30CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
Low · None · None
Fix status
Partial Red Hat: 19 fixed, 1 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-125 and the CVSS impact.

Summary

Out-of-bounds Read vulnerability in mod_proxy_ajp of Apache HTTP Server. This issue affects Apache HTTP Server: 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 0.00393 33rd percentileScored 2026-11-07
Fix Partial Red Hat: 14 advisoriesRed Hat: 19 fixed, 1 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 Serverup to 2.4.66—No fix listedCNA
  • Apache HTTP Server VendorApache Affected up to 2.4.66 Fixed in — No fix listed CNA

CPE configurations NVD · 1

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

Remediation

Red Hat 14 advisories

  • RHSA-2026:92590 Released 2026-10-29 · Red Hat rating Important
    httpd security update
    • Red Hat Enterprise Linux Server (v. 7 ELS) httpd-2.4.6-99.el7_9.8, mod_ssl-1:2.4.6-99.el7_9.8
    • Red Hat Enterprise Linux Server Optional (v. 7 ELS) mod_proxy_html-1:2.4.6-99.el7_9.8
  • RHSA-2026:67152 Released 2026-09-14 · Red Hat rating Important
    httpd security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) httpd-2.4.53-11.el9_2.15, httpd-core-2.4.53-11.el9_2.15, mod_ldap-2.4.53-11.el9_2.15 +2
  • RHSA-2026:66323 Released 2026-09-10 · Red Hat rating Important
    httpd security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) httpd-2.4.57-11.el9_4.5, httpd-core-2.4.57-11.el9_4.5, mod_ldap-2.4.57-11.el9_4.5 +2
Show 11 more Red Hat advisories
  • RHSA-2026:62165 Released 2026-09-01 · Red Hat rating Important
    httpd security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) httpd-2.4.62-4.el9_6.6, httpd-core-2.4.62-4.el9_6.6, httpd-devel-2.4.62-4.el9_6.6 +8
  • RHSA-2026:47046 Released 2026-07-28 · Red Hat rating Important
    httpd security update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) httpd-2.4.63-1.el10_0.4, httpd-core-2.4.63-1.el10_0.4, httpd-devel-2.4.63-1.el10_0.4 +8
  • RHSA-2026:36846 Released 2026-07-08 · Red Hat rating Important
    httpd:2.4 security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) httpd-2.4.37-39.module+el8.4.0+24495+1afced82.12.src::httpd:2.4, httpd-2.4.37-39.module+el8.4.0+24495+1afced82.12.x86_64::httpd:2.4, httpd-devel-2.4.37-39.module+el8.4.0+24495+1afced82.12.x86_64::httpd:2.4 +11
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) httpd-2.4.37-39.module+el8.4.0+24495+1afced82.12.src::httpd:2.4, httpd-2.4.37-39.module+el8.4.0+24495+1afced82.12.x86_64::httpd:2.4, httpd-devel-2.4.37-39.module+el8.4.0+24495+1afced82.12.x86_64::httpd:2.4 +11
  • RHSA-2026:36831 Released 2026-07-08 · Red Hat rating Important
    httpd:2.4 security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) httpd-2.4.37-47.module+el8.6.0+24496+af8fe930.13.src::httpd:2.4, httpd-2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64::httpd:2.4, httpd-devel-2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64::httpd:2.4 +11
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) httpd-2.4.37-47.module+el8.6.0+24496+af8fe930.13.src::httpd:2.4, httpd-2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64::httpd:2.4, httpd-devel-2.4.37-47.module+el8.6.0+24496+af8fe930.13.x86_64::httpd:2.4 +11
  • RHSA-2026:36373 Released 2026-07-07 · Red Hat rating Important
    httpd:2.4 security update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) httpd-2.4.37-56.module+el8.8.0+24497+e470c0e2.12.ppc64le::httpd:2.4, httpd-2.4.37-56.module+el8.8.0+24497+e470c0e2.12.src::httpd:2.4, httpd-2.4.37-56.module+el8.8.0+24497+e470c0e2.12.x86_64::httpd:2.4 +20
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) httpd-2.4.37-56.module+el8.8.0+24497+e470c0e2.12.src::httpd:2.4, httpd-2.4.37-56.module+el8.8.0+24497+e470c0e2.12.x86_64::httpd:2.4, httpd-devel-2.4.37-56.module+el8.8.0+24497+e470c0e2.12.x86_64::httpd:2.4 +11
  • RHSA-2026:27200 Released 2026-06-22 · Red Hat rating Important
    Red Hat JBoss Core Services Apache HTTP Server 2.4.62 SP4 security update
    • Red Hat JBoss Core Services on RHEL 7 Server jbcs-httpd24-httpd-2.4.62-13.el7jbcs, jbcs-httpd24-httpd-devel-2.4.62-13.el7jbcs, jbcs-httpd24-httpd-manual-2.4.62-13.el7jbcs +10
    • Red Hat JBoss Core Services on RHEL 8 jbcs-httpd24-httpd-2.4.62-13.el8jbcs, jbcs-httpd24-httpd-devel-2.4.62-13.el8jbcs, jbcs-httpd24-httpd-manual-2.4.62-13.el8jbcs +10
  • RHSA-2026:27201 Released 2026-06-22 · Red Hat rating Important
    Red Hat JBoss Core Services Apache HTTP Server 2.4.62 SP4 security update
    • Red Hat JBoss Core Services 2.4.62.SP4
  • RHSA-2026:22140 Released 2026-06-01 · Red Hat rating Important
    httpd:2.4 security update
    • Red Hat Enterprise Linux AppStream (v. 8) httpd-2.4.37-65.module+el8.10.0+24281+ea10630c.8.aarch64::httpd:2.4, httpd-2.4.37-65.module+el8.10.0+24281+ea10630c.8.ppc64le::httpd:2.4, httpd-2.4.37-65.module+el8.10.0+24281+ea10630c.8.s390x::httpd:2.4 +38
  • RHSA-2026:21433 Released 2026-05-27 · Red Hat rating Important
    httpd security update
    • Red Hat Enterprise Linux AppStream (v. 10) httpd-2.4.63-13.el10_2.1, httpd-core-2.4.63-13.el10_2.1, httpd-devel-2.4.63-13.el10_2.1 +8
  • RHSA-2026:21391 Released 2026-05-27 · Red Hat rating Important
    httpd security update
    • Red Hat Enterprise Linux AppStream (v. 9) httpd-2.4.62-13.el9_8.1, httpd-core-2.4.62-13.el9_8.1, httpd-devel-2.4.62-13.el9_8.1 +8
  • RHSA-2026:13938 Released 2026-05-06 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images httpd-2.4.67-0.1.hum1@aarch64, httpd-2.4.67-0.1.hum1@src, httpd-2.4.67-0.1.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 6AffectedNo fix yet
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:21433
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2026:22140
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:21391
Red Hat Enterprise Linux AppStream AUS (v.8.4)Fixed RHSA-2026:36846
Red Hat Enterprise Linux AppStream AUS (v.8.6)Fixed RHSA-2026:36831
Red Hat Enterprise Linux AppStream E4S (v.8.8)Fixed RHSA-2026:36373
Red Hat Enterprise Linux AppStream E4S (v.9.2)Fixed RHSA-2026:67152
Red Hat Enterprise Linux AppStream E4S (v.9.4)Fixed RHSA-2026:66323
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:47046
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:62165
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)Fixed RHSA-2026:36846
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)Fixed RHSA-2026:36831
Red Hat Enterprise Linux AppStream TUS (v.8.8)Fixed RHSA-2026:36373
Red Hat Enterprise Linux Server (v. 7 ELS)Fixed RHSA-2026:92590
Red Hat Enterprise Linux Server Optional (v. 7 ELS)Fixed RHSA-2026:92590
Red Hat Hardened ImagesFixed RHSA-2026:13938
Red Hat JBoss Core Services 2.4.62.SP4Fixed RHSA-2026:27201
Red Hat JBoss Core Services on RHEL 7 ServerFixed RHSA-2026:27200
Red Hat JBoss Core Services on RHEL 8Fixed RHSA-2026:27200
Not affected: 7 products
  • Red Hat Enterprise Linux AppStream E4S (v.9.2)
  • Red Hat Enterprise Linux AppStream E4S (v.9.4)
  • Red Hat Enterprise Linux Server (v. 7 ELS)
  • Red Hat Enterprise Linux Server Optional (v. 7 ELS)
  • Red Hat Hardened Images
  • Red Hat JBoss Core Services on RHEL 7 Server
  • Red Hat JBoss Core Services on RHEL 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-33857
  2. 2026-10-03 Alias added: GHSA-v5qg-p44g-5728
  3. 2026-10-09 Fix available: RHSA-2026:27201 · Red Hat
  4. 2026-10-09 Fix available: Red Hat JBoss Core Services 2.4.62.SP4 · Red Hat
  5. 2026-10-25 EPSS moved to the below the 50th percentile
  6. 2026-10-30 Fix available: RHSA-2026:92590 · Red Hat
  7. 2026-10-30 Fix available: Red Hat Enterprise Linux Server (v. 7 ELS), Red Hat Enterprise Linux Server Optional (v. 7 ELS) · 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