CVE-2025-53020 | Apache HTTP Server: HTTP/2 DoS by Memory Increase

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.

Published: 2025-07-10 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-53020 is rated Moderate Risk (62.6/100): CVSS High severity, with high exploitation likelihood (EPSS 4.41%, 90th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +1.09% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-53020

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-23 3.32% 4.41% +1.09%
2 2026-06-15 4.61% 3.32% -1.28%
3 2026-06-10 — 4.61% —

Full EPSS history (32 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-53020

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2025-53020

OS Trackers for CVE-2025-53020

vendor priority summary link
alpine — CVE-2025-53020: 1 source package rows (apache2); 5 state rows across 5 repos (3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 5, open 0. https://security.alpinelinux.org/vuln/CVE-2025-53020
debian not yet assigned CVE-2025-53020 not yet assigned priority: Debian including 1 source packages (apache2), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2025-53020
redhat medium — https://access.redhat.com/security/cve/CVE-2025-53020
suse medium — https://www.suse.com/security/cve/CVE-2025-53020/
ubuntu medium CVE-2025-53020 medium priority: Ubuntu including 1 source packages (apache2), 8 status rows across 8 suites (bionic, focal, jammy, noble, plucky, trusty, upstream, xenial): released 7, not-affected 1. https://ubuntu.com/security/CVE-2025-53020

Affected software / configurations for CVE-2025-53020

Vendor Product Version Raw CPE
apache http_server >= 2.4.17, < 2.4.64 cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*

References for CVE-2025-53020

cvelogic Threat Intelligence