CVE-2025-55753

HIGH

Apache HTTP Server <2.4.66 - DoS

Title source: llm
STIX 2.1

Description

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.

Scores

CVSS v3 7.5
EPSS 0.0010
EPSS Percentile 27.9%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-190
Status published
Products (1)
apache/http_server 2.4.30 - 2.4.66
Published Dec 05, 2025
Tracked Since Feb 18, 2026