CVE-2021-41773 in apache http server
LogPulse has a published detection rule for this CVE: it raises a notable when someone tries to exploit it.
What the vulnerability is
A flaw was found in a change made to path normalization in Apache HTTP Server 2.4.49. An attacker could use a path traversal attack to map URLs to files outside the directories configured by Alias-like directives. If files outside of these directories are not protected by the usual default configuration "require all denied", these requests can succeed. If CGI scripts are also enabled for these aliased pathes, this could allow for remote code execution. This issue is known to be exploited in the wild. This issue only affects Apache 2.4.49 and not earlier versions. The fix in Apache HTTP Server 2.4.50 was found to be incomplete, see CVE-2021-42013.
Affected software: apache http server, fedoraproject fedora, oracle instantis enterprisetrack, netapp cloud backup
Scores
- CVSS: 9.8 (critical)
- EPSS: 99.99% chance of exploitation in the next 30 days
- CISA KEV: Known exploited, listed 2021-11-03, used in ransomware
- Published: 2021-10-05
What LogPulse has for it
- Detection rule: Yes, published
- Agent check (vulnerable version): Yes, published
- Mitigation: No
Source data: NIST NVD, CISA KEV and FIRST EPSS. LogPulse processes new CVEs every hour.
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