Vulnerability record · CVE-2012-0021 · published 28 January 2012
CVE-2012-0021: Apache http server improper input validation vulnerability
Apache · Http Server
The log_cookie function in mod_log_config.c in the mod_log_config module in the Apache HTTP Server 2.2.17 through 2.2.21, when a threaded MPM is used, does not properly handle a %{}C format string, which allows remote attackers to cause a denial of service (daemon crash) via a cookie that lacks both a name and a value.
Description
The log_cookie function in mod_log_config.c in the mod_log_config module in the Apache HTTP Server 2.2.17 through 2.2.21, when a threaded MPM is used, does not properly handle a %{}C format string, which allows remote attackers to cause a denial of service (daemon crash) via a cookie that lacks both a name and a value.
AV:N/AC:H/Au:N/C:N/I:N/A:P
Affected products
1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2012-0021), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.
