Cyber Resilience

CVE-2025-53020

Apache Http Server 2.4.17 – 2.4.64

Published
10 July 2025
Modified
17 June 2026
Patch / advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.046 91th percentile
Risk Priority 64 floored blend · peak EPSS

Summary

CVE-2025-53020 is a high-severity Missing Release of Memory after Effective Lifetime (CWE-401) vulnerability in Apache Http Server. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Endpoint Denial of Service (T1499); ranked in the top 9% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-15 (Development Process, Standards, and Tools) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2025-53020 is a Late Release of Memory after Effective Lifetime vulnerability, assigned CWE-401, that affects Apache HTTP Server versions 2.4.17 through 2.4.63. The flaw carries a CVSS 3.1 base score of 7.5 and results in high availability impact without affecting confidentiality or integrity.

An unauthenticated remote attacker can send crafted requests over the network to trigger the memory-handling error, leading to resource exhaustion or service disruption on the affected server. No user interaction or credentials are required for exploitation.

Advisories from the Apache project and downstream distributions such as Debian recommend upgrading immediately to version 2.4.64, which resolves the issue; the Apache security page and oss-security mailing list provide the official patch and release notes.

The associated EPSS score remains flat at 0.0461 with no material increase after disclosure.

EU & UK References

Vulnerability Data

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.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
T1499.003 Application Exhaustion Flood Impact
Adversaries may target resource intensive features of applications to cause a denial of service (DoS), denying availability to those applications.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

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CVE-2026-29169Same product: Apache Http Server
CVE-2026-23918Same product: Apache Http Server
CVE-2026-43951Same product: Apache Http Server
CVE-2024-41172Same vendor: Apache
CVE-2026-34032Same product: Apache Http Server

Affected Assets

apache
http server
2.4.17 — 2.4.64

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation (static analysis, fuzzing, or runtime leak detection) directly finds missing deallocation.

Requiring documented development standards and tools can mandate memory-management disciplines that avoid leaks at introduction.

Engineering principles applied during development can require explicit resource-release patterns that stop memory leaks from being coded.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly enforce proper memory allocation/deallocation via coding standards, reviews, and tooling.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing in development can detect unreleased memory, providing partial coverage of the weakness.

prevents

Secure development life cycle mandates memory-management practices that reduce missing-release defects.

prevents

Application security requirements can specify explicit memory-release rules, partially mitigating the weakness.

prevents

Secure system architecture and engineering principles include resource-management guidelines that address memory leaks.

prevents

Secure coding standards directly require proper allocation/deallocation, covering most of this weakness.

finds

Capacity management may detect memory exhaustion symptoms but does not prevent the coding flaw.

References