TI-2025-33022 Aliases CVE-2025-53020 GHSA-c2vf-6g7v-8m6c

Apache HTTP Server: HTTP/2 DoS by Memory Increase

MEDIUM 47CWE-401Published 2025-07-10 · Updated 2025-11-04

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · High
Fix status: Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-401.

Summary

Late Release of Memory after Effective Lifetime vulnerability in Apache HTTP Server. This issue affects Apache HTTP Server: from 2.4.17 up to 2.4.63. Users are recommended to upgrade to version 2.4.64, which fixes the issue.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.04963 92nd percentileScored 2026-11-07

Fix Fixed Red Hat: 12 advisories

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

Vendor	Product	Affected versions	Fixed in	Status	Source
Apache	Apache HTTP Server	2.4.17 – 2.4.63	—	No fix listed	CNA

Apache HTTP Server VendorApache Affected 2.4.17 – 2.4.63 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:apache:http_server::::::::	2.4.17 to before 2.4.64	Vulnerable	Apache

cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:* Versions 2.4.17 to before 2.4.64 Vulnerable ·Apache

Remediation

Red Hat 12 advisories

RHSA-2026:55992 Released 2026-08-18 · Red Hat rating Important
mod_http2 security update
- Red Hat Enterprise Linux AppStream E4S (v.9.4) mod_http2-2.0.26-2.el9_4.3
RHSA-2026:55930 Released 2026-08-18 · Red Hat rating Important
mod_http2 security update
- Red Hat Enterprise Linux AppStream E4S (v.9.2) mod_http2-1.15.19-4.el9_2.8
RHSA-2026:50572 Released 2026-08-05 · Red Hat rating Important
mod_http2 security update
- Red Hat Enterprise Linux AppStream EUS (v.9.6) mod_http2-2.0.26-4.el9_6.2

Show 9 more Red Hat advisories

RHSA-2026:50538 Released 2026-08-05 · Red Hat rating Important
mod_http2 security update
- Red Hat Enterprise Linux AppStream EUS (v. 10.0) mod_http2-2.0.29-2.el10_0.2
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-2026:22551 Released 2026-06-03 · Red Hat rating Moderate
mod_http2 security update
- Red Hat Enterprise Linux AppStream (v. 9) mod_http2-2.0.26-6.el9_8
RHSA-2026:22528 Released 2026-06-03 · Red Hat rating Moderate
mod_http2 security update
- Red Hat Enterprise Linux AppStream (v. 10) mod_http2-2.0.29-4.el10_2
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

Vendor assessments

Red Hat

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

Product	Status	Plan or fix
Red Hat Enterprise Linux AppStream (v. 10)	Fixed	RHSA-2026:22528
Red Hat Enterprise Linux AppStream (v. 8)	Fixed	RHSA-2026:22140
Red Hat Enterprise Linux AppStream (v. 9)	Fixed	RHSA-2026:22551
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-2026:55930
Red Hat Enterprise Linux AppStream E4S (v.9.4)	Fixed	RHSA-2026:55992
Red Hat Enterprise Linux AppStream EUS (v. 10.0)	Fixed	RHSA-2026:50538
Red Hat Enterprise Linux AppStream EUS (v.9.6)	Fixed	RHSA-2026:50572
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 JBoss Core Services 2.4.62.SP4	Fixed	RHSA-2026:27201
Red Hat JBoss Core Services on RHEL 7 Server	Fixed	RHSA-2026:27200
Red Hat JBoss Core Services on RHEL 8	Fixed	RHSA-2026:27200

Not affected: 8 products

Red Hat Enterprise Linux 6
Red Hat Enterprise Linux 7
Red Hat Enterprise Linux AppStream E4S (v.9.2)
Red Hat Enterprise Linux AppStream E4S (v.9.4)
Red Hat Enterprise Linux AppStream EUS (v. 10.0)
Red Hat Enterprise Linux AppStream EUS (v.9.6)
Red Hat JBoss Core Services on RHEL 7 Server
Red Hat JBoss Core Services on RHEL 8

Timeline

2026-10-02 Threatist record created from CVE-2025-53020
2026-10-03 Alias added: GHSA-c2vf-6g7v-8m6c
2026-10-09 Fix available: RHSA-2026:27201 · Red Hat
2026-10-16 Fix available: Red Hat JBoss Core Services 2.4.62.SP4 · Red Hat

References

Advisory 1

https://httpd.apache.org/security/vulnerabilities_24.html

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