CVE-2011-3639

medium

Published 2011-11-30 · Modified 2026-04-29

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CVSS v3

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CVSS v4 NEW

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not yet in upstream

VIR risk

5.3

Description

The mod_proxy module in the Apache HTTP Server 2.0.x through 2.0.64 and 2.2.x before 2.2.18, when the Revision 1179239 patch is in place, does not properly interact with use of (1) RewriteRule and (2) ProxyPassMatch pattern matches for configuration of a reverse proxy, which allows remote attackers to send requests to intranet servers by using the HTTP/0.9 protocol with a malformed URI containing an initial @ (at sign) character. NOTE: this vulnerability exists because of an incomplete fix for CVE-2011-3368.

Predictions

Exploit likelihood

55%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

Exploits

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

Exploit-DB

EDB-36663 remote linux verified

Tomas Hoger · 2012-02-06

Apache 2.2.15 mod_proxy - Reverse Proxy Security Bypass

Source code queued for fetch — refresh in a moment.

OS impact

Debian Fixed 5 releases

Version	Status	Fixed in
trixie	Fixed	`2.2.18-1`
sid	Fixed	`2.2.18-1`
forky	Fixed	`2.2.18-1`
bullseye	Fixed	`2.2.18-1`
bookworm	Fixed	`2.2.18-1`

Application impact

Vendor	Product	Versions
apache	http_server	`2.0.11`
apache	http_server	`2.0.12`
apache	http_server	`2.0.13`
apache	http_server	`2.0.14`
apache	http_server	`2.0.15`
apache	http_server	`2.0.16`
apache	http_server	`2.0.17`
apache	http_server	`2.0.18`
apache	http_server	`2.0.19`
apache	http_server	`2.0.20`
apache	http_server	`2.0.21`
apache	http_server	`2.0.22`
apache	http_server	`2.0.23`
apache	http_server	`2.0.24`
apache	http_server	`2.0.25`
apache	http_server	`2.0.26`
apache	http_server	`2.0.27`
apache	http_server	`2.0.28`
apache	http_server	`2.0.29`
apache	http_server	`2.0.30`
apache	http_server	`2.0.31`
apache	http_server	`2.0.32`
apache	http_server	`2.0.33`
apache	http_server	`2.0.34`
apache	http_server	`2.0.35`
apache	http_server	`2.0.36`
apache	http_server	`2.0.37`
apache	http_server	`2.0.38`
apache	http_server	`2.0.39`
apache	http_server	`2.0.40`
apache	http_server	`2.0.41`
apache	http_server	`2.0.42`
apache	http_server	`2.0.43`
apache	http_server	`2.0.44`
apache	http_server	`2.0.45`
apache	http_server	`2.0.46`
apache	http_server	`2.0.47`
apache	http_server	`2.0.48`
apache	http_server	`2.0.49`
apache	http_server	`2.0.50`
apache	http_server	`2.0.51`
apache	http_server	`2.0.52`
apache	http_server	`2.0.53`
apache	http_server	`2.0.54`
apache	http_server	`2.0.55`
apache	http_server	`2.0.56`
apache	http_server	`2.0.57`
apache	http_server	`2.0.58`
apache	http_server	`2.0.59`
apache	http_server	`2.0.61`
apache	http_server	`2.0.63`
apache	http_server	`2.2.0`
apache	http_server	`2.2.1`
apache	http_server	`2.2.2`
apache	http_server	`2.2.3`
apache	http_server	`2.2.4`
apache	http_server	`2.2.6`
apache	http_server	`2.2.8`
apache	http_server	`2.2.9`
apache	http_server	`2.2.10`
apache	http_server	`2.2.11`
apache	http_server	`2.2.12`
apache	http_server	`2.2.13`
apache	http_server	`2.2.14`
apache	http_server	`2.2.15`
apache	http_server	`2.2.16`
apache	http_server	`2.2.17`
apache	http_server2.0a1
apache	http_server2.0a2
apache	http_server2.0a3
apache	http_server2.0a4
apache	http_server2.0a5
apache	http_server2.0a6
apache	http_server2.0a7
apache	http_server2.0a8
apache	http_server2.0a9

References

CWEs

CWE-20

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.