CVE-2012-4557

CVE-2012-4557 is a medium-severity vulnerability in Apache Http Server with a CVSS 2.0 base score of 5.0. Its EPSS exploit-prediction score of 17% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-399.

Key facts

Description

The mod_proxy_ajp module in the Apache HTTP Server 2.2.12 through 2.2.21 places a worker node into an error state upon detection of a long request-processing time, which allows remote attackers to cause a denial of service (worker consumption) via an expensive request.

Frequently asked questions

What is CVE-2012-4557?
The mod_proxy_ajp module in the Apache HTTP Server 2.2.12 through 2.2.21 places a worker node into an error state upon detection of a long request-processing time, which allows remote attackers to cause a denial of service (worker consumption) via an expensive request.
How severe is CVE-2012-4557?
CVE-2012-4557 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2012-4557 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 17% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2012-4557?
CVE-2012-4557 primarily affects Apache Http Server. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2012-4557?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2012-4557 published?
CVE-2012-4557 was published on 2012-11-30 and last updated on 2026-06-16.

References

Affected products (10)

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Threat intelligence

Threat-intel indicators referencing this CVE: