Home/CVE/An integer overflow in the case of failed ACME certificate renewal leads, after a number of failures (~30 days in defaul
CVE

CVE-2025-55753

An integer overflow in the case of failed ACME certificate renewal leads, after a number of failures (~30 days in defaul

An integer overflow in the case of failed ACME certificate renewal leads, after a number of failures (~30 days in default configurations), to the backoff timer becoming 0. Attempts to renew the certificate then are repeated without delays until it succeeds. This issue affects Apache HTTP Server: from 2.4.30 before 2.4.66.

Users are recommended to upgrade to version 2.4.66, which fixes the issue.

HIGH · CVSS 7.5 EPSS 0.00048
Schedule remediation
  • CVSS base score ≥ 7.0
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-190Integer Overflow or Wraparound
▤

Affected Products & Versions

1
apache http server>= 2.4.30 and < 2.4.66
▣

Scoring & Timeline

7.5
HIGH · CVSS v3.1 · security@apache.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD05 Dec 2025 · 11:15 AM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC triage · cisa-vulnrichment
Exploitation
none
Automatable
no
Technical impact
partial
SSVC asks the questions that actually drive patch urgency: is it being exploited, can attacks be automated, and how total is the impact.
⚑

Vendor Advisories

27
apple-security126794
apple-security126795
apple-security126796
rhsaRHSA-2026:2995Important
rhsaRHSA-2026:2994Important
🔗

References & Sources

2
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://httpd.apache.org/security/vulnerabilities_24.htmlVendor Advisory
http://www.openwall.com/lists/oss-security/2025/12/04/4Issue TrackingThird Party Advisory
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