CVE-2021-42013

critical KEV

Published 2021-11-03 · Modified 2021-11-03

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CVSS v3

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CVSS v4 NEW

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not yet in upstream

VIR risk

10.0

Description

It was found that the fix for CVE-2021-41773 in Apache HTTP Server 2.4.50 was insufficient. 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 only affects Apache 2.4.49 and Apache 2.4.50 and not earlier versions.

CISA KEV

Vendor: Apache
Product: HTTP Server
Due date: 2021-11-17

Predictions

Exploit likelihood

99%

Patch ETA

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Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

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Exploits

Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.