VIR Vulnerability Intelligence Relay

CVE-2011-4317

medium
Published 2011-11-30 · Modified 2026-04-29
💬 Discuss on Community ✚ Propose mitigation
CVSS v3
—
CVSS v4 NEW
—
not yet in upstream
VIR risk
5.3

Description

The mod_proxy module in the Apache HTTP Server 1.3.x through 1.3.42, 2.0.x through 2.0.64, and 2.2.x through 2.2.21, 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 via a malformed URI containing an @ (at sign) character and a : (colon) character in invalid positions. 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-36352 remote linux verified text · 1 KB
Prutha Parikh · 2011-11-24

Apache 7.0.x mod_proxy - Reverse Proxy Security Bypass

text exploit Source: Exploit-DB 
source: https://www.securityfocus.com/bid/50802/info

Apache HTTP Server is prone to a security-bypass vulnerability.

Successful exploits will allow attackers to bypass certain security restrictions and obtain sensitive information about running web applications. 

The following example patterns are available:

RewriteRule ^(.*) http://www.example.com$1
ProxyPassMatch ^(.*) http://www.example.com$1

OS impact
debian Debian Fixed 5 releases
VersionStatusFixed in
trixie Fixed 2.2.21-3
sid Fixed 2.2.21-3
forky Fixed 2.2.21-3
bullseye Fixed 2.2.21-3
bookworm Fixed 2.2.21-3

Application impact
VendorProductVersionsFixed
apache apachehttp_server1.3
apache apachehttp_server1.3.0
apache apachehttp_server1.3.1
apache apachehttp_server1.3.1.1
apache apachehttp_server1.3.2
apache apachehttp_server1.3.3
apache apachehttp_server1.3.4
apache apachehttp_server1.3.5
apache apachehttp_server1.3.6
apache apachehttp_server1.3.7
apache apachehttp_server1.3.8
apache apachehttp_server1.3.9
apache apachehttp_server1.3.10
apache apachehttp_server1.3.11
apache apachehttp_server1.3.12
apache apachehttp_server1.3.13
apache apachehttp_server1.3.14
apache apachehttp_server1.3.15
apache apachehttp_server1.3.16
apache apachehttp_server1.3.17
apache apachehttp_server1.3.18
apache apachehttp_server1.3.19
apache apachehttp_server1.3.20
apache apachehttp_server1.3.22
apache apachehttp_server1.3.23
apache apachehttp_server1.3.24
apache apachehttp_server1.3.25
apache apachehttp_server1.3.26
apache apachehttp_server1.3.27
apache apachehttp_server1.3.28
apache apachehttp_server1.3.29
apache apachehttp_server1.3.30
apache apachehttp_server1.3.31
apache apachehttp_server1.3.32
apache apachehttp_server1.3.33
apache apachehttp_server1.3.34
apache apachehttp_server1.3.35
apache apachehttp_server1.3.36
apache apachehttp_server1.3.37
apache apachehttp_server1.3.38
apache apachehttp_server1.3.39
apache apachehttp_server1.3.41
apache apachehttp_server1.3.42
apache apachehttp_server1.3.65
apache apachehttp_server1.3.68
apache apachehttp_server2.0
apache apachehttp_server2.0.9
apache apachehttp_server2.0.28
apache apachehttp_server2.0.32
apache apachehttp_server2.0.34
apache apachehttp_server2.0.35
apache apachehttp_server2.0.36
apache apachehttp_server2.0.37
apache apachehttp_server2.0.38
apache apachehttp_server2.0.39
apache apachehttp_server2.0.40
apache apachehttp_server2.0.41
apache apachehttp_server2.0.42
apache apachehttp_server2.0.43
apache apachehttp_server2.0.44
apache apachehttp_server2.0.45
apache apachehttp_server2.0.46
apache apachehttp_server2.0.47
apache apachehttp_server2.0.48
apache apachehttp_server2.0.49
apache apachehttp_server2.0.50
apache apachehttp_server2.0.51
apache apachehttp_server2.0.52
apache apachehttp_server2.0.53
apache apachehttp_server2.0.54
apache apachehttp_server2.0.55
apache apachehttp_server2.0.56
apache apachehttp_server2.0.57
apache apachehttp_server2.0.58
apache apachehttp_server2.0.59
apache apachehttp_server2.0.60
apache apachehttp_server2.0.61
apache apachehttp_server2.0.63
apache apachehttp_server2.0.64
apache apachehttp_server2.2.0
apache apachehttp_server2.2.1
apache apachehttp_server2.2.2
apache apachehttp_server2.2.3
apache apachehttp_server2.2.4
apache apachehttp_server2.2.6
apache apachehttp_server2.2.8
apache apachehttp_server2.2.9
apache apachehttp_server2.2.10
apache apachehttp_server2.2.11
apache apachehttp_server2.2.12
apache apachehttp_server2.2.13
apache apachehttp_server2.2.14
apache apachehttp_server2.2.15
apache apachehttp_server2.2.16
apache apachehttp_server2.2.18
apache apachehttp_server2.2.19
apache apachehttp_server2.2.20
apache apachehttp_server2.2.21

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.