Integer Overflow Vulnerability in Apache HTTP Server

CVE-2025-55753

What is CVE-2025-55753?

An integer overflow vulnerability exists in Apache HTTP Server that occurs during ACME certificate renewal processes. If renewal attempts fail several times, the backoff timer can reset to zero after approximately 30 days in default configurations. This results in repeated attempts to renew the certificate without any delay, potentially leading to excessive requests and service disruptions. To mitigate this risk, users are advised to update to Apache HTTP Server version 2.4.66 or later, which addresses this issue.

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