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                             CERT-Renater

                 Note d'Information No. 2021/VULN525
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DATE                : 08/10/2021

HARDWARE PLATFORM(S): /

OPERATING SYSTEM(S): Systems running Apache HTTP Server versions 2.4.49,
                                          2.4.50.

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http://mail-archives.apache.org/mod_mbox/www-announce/202110.mbox/%3c7c4d9498-09ce-c4b4-b1c7-d55512fdc0b0@apache.org%3e
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CVE-2021-42013: Path Traversal and Remote Code Execution in Apache HTTP
Server 2.4.49 and 2.4.50 (incomplete fix of CVE-2021-41773)

Severity: critical

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.


Credit:

Reported by Juan Escobar from Dreamlab Technologies, Fernando Muñoz from
NULL Life CTF Team, and Shungo Kumasaka


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+ 23/25 Rue Daviel   |    fax : 01-53-94-20-41          +
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