CVE-2011-4317

Exp

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.

Published: 2011-11-30 Last update: 2026-04-29 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2011-4317 is rated High Exploit Risk (64.4/100): CVSS Medium severity, with high exploitation likelihood (EPSS 79.45%, 99th percentile). 3 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2011-4317

EDB-ID Source Kind Published Link
36352 exploit_db edb 2011-11-24 Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2011-4317

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-29 81.92% 79.45% -2.47%
2 2026-03-19 84.29% 81.92% -2.37%
3 2026-03-04 — 84.29% —

Full EPSS history (51 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2011-4317

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:N/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 8.6 2.9 [email protected]

Weakness enumeration for CVE-2011-4317

OS Trackers for CVE-2011-4317

vendor priority summary link
debian not yet assigned CVE-2011-4317 not yet assigned priority: Debian including 1 source packages (apache2), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2011-4317
gentoo high CVE-2011-4317: 1 GLSA(s) (201206-25), 1 atom(s) (www-servers/apache); latest impact high. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2011-4317
redhat medium — https://access.redhat.com/security/cve/CVE-2011-4317
suse medium CVE-2011-4317 severity moderate: SUSE including 93 source package names (apache2-2.2.12-1.28.1, apache2-2.2.12-1.38.2, …), 123 product×package rows across 25 product lines (SUSE Linux Enterprise High Performance Computing 12 SP5, SUSE Linux Enterprise Module for Server Applications 15, … (25 product lines)): Fixed 123. https://www.suse.com/security/cve/CVE-2011-4317/
ubuntu medium CVE-2011-4317 medium priority: Ubuntu including 1 source packages (apache2), 6 status rows across 6 suites (hardy, lucid, maverick, natty, oneiric, upstream): released 5, needs-triage 1. https://ubuntu.com/security/CVE-2011-4317

Affected software / configurations for CVE-2011-4317

Vendor Product Version Raw CPE
apache http_server 1.3 cpe:2.3:a:apache:http_server:1.3:*:*:*:*:*:*:*
apache http_server 1.3.0 cpe:2.3:a:apache:http_server:1.3.0:*:*:*:*:*:*:*
apache http_server 1.3.1 cpe:2.3:a:apache:http_server:1.3.1:*:*:*:*:*:*:*
apache http_server 1.3.1.1 cpe:2.3:a:apache:http_server:1.3.1.1:*:*:*:*:*:*:*
apache http_server 1.3.2 cpe:2.3:a:apache:http_server:1.3.2:*:*:*:*:*:*:*
apache http_server 1.3.3 cpe:2.3:a:apache:http_server:1.3.3:*:*:*:*:*:*:*
apache http_server 1.3.4 cpe:2.3:a:apache:http_server:1.3.4:*:*:*:*:*:*:*
apache http_server 1.3.5 cpe:2.3:a:apache:http_server:1.3.5:*:*:*:*:*:*:*
apache http_server 1.3.6 cpe:2.3:a:apache:http_server:1.3.6:*:*:*:*:*:*:*
apache http_server 1.3.7 cpe:2.3:a:apache:http_server:1.3.7:*:*:*:*:*:*:*
apache http_server 1.3.8 cpe:2.3:a:apache:http_server:1.3.8:*:*:*:*:*:*:*
apache http_server 1.3.9 cpe:2.3:a:apache:http_server:1.3.9:*:*:*:*:*:*:*
apache http_server 1.3.10 cpe:2.3:a:apache:http_server:1.3.10:*:*:*:*:*:*:*
apache http_server 1.3.11 cpe:2.3:a:apache:http_server:1.3.11:*:*:*:*:*:*:*
apache http_server 1.3.12 cpe:2.3:a:apache:http_server:1.3.12:*:*:*:*:*:*:*
apache http_server 1.3.13 cpe:2.3:a:apache:http_server:1.3.13:*:*:*:*:*:*:*
apache http_server 1.3.14 cpe:2.3:a:apache:http_server:1.3.14:*:*:*:*:*:*:*
apache http_server 1.3.15 cpe:2.3:a:apache:http_server:1.3.15:*:*:*:*:*:*:*
apache http_server 1.3.16 cpe:2.3:a:apache:http_server:1.3.16:*:*:*:*:*:*:*
apache http_server 1.3.17 cpe:2.3:a:apache:http_server:1.3.17:*:*:*:*:*:*:*
apache http_server 1.3.18 cpe:2.3:a:apache:http_server:1.3.18:*:*:*:*:*:*:*
apache http_server 1.3.19 cpe:2.3:a:apache:http_server:1.3.19:*:*:*:*:*:*:*
apache http_server 1.3.20 cpe:2.3:a:apache:http_server:1.3.20:*:*:*:*:*:*:*
apache http_server 1.3.22 cpe:2.3:a:apache:http_server:1.3.22:*:*:*:*:*:*:*
apache http_server 1.3.23 cpe:2.3:a:apache:http_server:1.3.23:*:*:*:*:*:*:*
apache http_server 1.3.24 cpe:2.3:a:apache:http_server:1.3.24:*:*:*:*:*:*:*
apache http_server 1.3.25 cpe:2.3:a:apache:http_server:1.3.25:*:*:*:*:*:*:*
apache http_server 1.3.26 cpe:2.3:a:apache:http_server:1.3.26:*:*:*:*:*:*:*
apache http_server 1.3.27 cpe:2.3:a:apache:http_server:1.3.27:*:*:*:*:*:*:*
apache http_server 1.3.28 cpe:2.3:a:apache:http_server:1.3.28:*:*:*:*:*:*:*
apache http_server 1.3.29 cpe:2.3:a:apache:http_server:1.3.29:*:*:*:*:*:*:*
apache http_server 1.3.30 cpe:2.3:a:apache:http_server:1.3.30:*:*:*:*:*:*:*
apache http_server 1.3.31 cpe:2.3:a:apache:http_server:1.3.31:*:*:*:*:*:*:*
apache http_server 1.3.32 cpe:2.3:a:apache:http_server:1.3.32:*:*:*:*:*:*:*
apache http_server 1.3.33 cpe:2.3:a:apache:http_server:1.3.33:*:*:*:*:*:*:*
apache http_server 1.3.34 cpe:2.3:a:apache:http_server:1.3.34:*:*:*:*:*:*:*
apache http_server 1.3.35 cpe:2.3:a:apache:http_server:1.3.35:*:*:*:*:*:*:*
apache http_server 1.3.36 cpe:2.3:a:apache:http_server:1.3.36:*:*:*:*:*:*:*
apache http_server 1.3.37 cpe:2.3:a:apache:http_server:1.3.37:*:*:*:*:*:*:*
apache http_server 1.3.38 cpe:2.3:a:apache:http_server:1.3.38:*:*:*:*:*:*:*
apache http_server 1.3.39 cpe:2.3:a:apache:http_server:1.3.39:*:*:*:*:*:*:*
apache http_server 1.3.41 cpe:2.3:a:apache:http_server:1.3.41:*:*:*:*:*:*:*
apache http_server 1.3.42 cpe:2.3:a:apache:http_server:1.3.42:*:*:*:*:*:*:*
apache http_server 1.3.65 cpe:2.3:a:apache:http_server:1.3.65:*:*:*:*:*:*:*
apache http_server 1.3.68 cpe:2.3:a:apache:http_server:1.3.68:*:*:*:*:*:*:*
apache http_server 2.0 cpe:2.3:a:apache:http_server:2.0:*:*:*:*:*:*:*
apache http_server 2.0.9 cpe:2.3:a:apache:http_server:2.0.9:*:*:*:*:*:*:*
apache http_server 2.0.28 cpe:2.3:a:apache:http_server:2.0.28:*:*:*:*:*:*:*
apache http_server 2.0.28 cpe:2.3:a:apache:http_server:2.0.28:beta:*:*:*:*:*:*
apache http_server 2.0.32 cpe:2.3:a:apache:http_server:2.0.32:*:*:*:*:*:*:*
apache http_server 2.0.32 cpe:2.3:a:apache:http_server:2.0.32:beta:*:*:*:*:*:*
apache http_server 2.0.34 cpe:2.3:a:apache:http_server:2.0.34:beta:*:*:*:*:*:*
apache http_server 2.0.35 cpe:2.3:a:apache:http_server:2.0.35:*:*:*:*:*:*:*
apache http_server 2.0.36 cpe:2.3:a:apache:http_server:2.0.36:*:*:*:*:*:*:*
apache http_server 2.0.37 cpe:2.3:a:apache:http_server:2.0.37:*:*:*:*:*:*:*
apache http_server 2.0.38 cpe:2.3:a:apache:http_server:2.0.38:*:*:*:*:*:*:*
apache http_server 2.0.39 cpe:2.3:a:apache:http_server:2.0.39:*:*:*:*:*:*:*
apache http_server 2.0.40 cpe:2.3:a:apache:http_server:2.0.40:*:*:*:*:*:*:*
apache http_server 2.0.41 cpe:2.3:a:apache:http_server:2.0.41:*:*:*:*:*:*:*
apache http_server 2.0.42 cpe:2.3:a:apache:http_server:2.0.42:*:*:*:*:*:*:*
apache http_server 2.0.43 cpe:2.3:a:apache:http_server:2.0.43:*:*:*:*:*:*:*
apache http_server 2.0.44 cpe:2.3:a:apache:http_server:2.0.44:*:*:*:*:*:*:*
apache http_server 2.0.45 cpe:2.3:a:apache:http_server:2.0.45:*:*:*:*:*:*:*
apache http_server 2.0.46 cpe:2.3:a:apache:http_server:2.0.46:*:*:*:*:*:*:*
apache http_server 2.0.47 cpe:2.3:a:apache:http_server:2.0.47:*:*:*:*:*:*:*
apache http_server 2.0.48 cpe:2.3:a:apache:http_server:2.0.48:*:*:*:*:*:*:*
apache http_server 2.0.49 cpe:2.3:a:apache:http_server:2.0.49:*:*:*:*:*:*:*
apache http_server 2.0.50 cpe:2.3:a:apache:http_server:2.0.50:*:*:*:*:*:*:*
apache http_server 2.0.51 cpe:2.3:a:apache:http_server:2.0.51:*:*:*:*:*:*:*
apache http_server 2.0.52 cpe:2.3:a:apache:http_server:2.0.52:*:*:*:*:*:*:*
apache http_server 2.0.53 cpe:2.3:a:apache:http_server:2.0.53:*:*:*:*:*:*:*
apache http_server 2.0.54 cpe:2.3:a:apache:http_server:2.0.54:*:*:*:*:*:*:*
apache http_server 2.0.55 cpe:2.3:a:apache:http_server:2.0.55:*:*:*:*:*:*:*
apache http_server 2.0.56 cpe:2.3:a:apache:http_server:2.0.56:*:*:*:*:*:*:*
apache http_server 2.0.57 cpe:2.3:a:apache:http_server:2.0.57:*:*:*:*:*:*:*
apache http_server 2.0.58 cpe:2.3:a:apache:http_server:2.0.58:*:*:*:*:*:*:*
apache http_server 2.0.59 cpe:2.3:a:apache:http_server:2.0.59:*:*:*:*:*:*:*
apache http_server 2.0.60 cpe:2.3:a:apache:http_server:2.0.60:*:*:*:*:*:*:*
apache http_server 2.0.61 cpe:2.3:a:apache:http_server:2.0.61:*:*:*:*:*:*:*
apache http_server 2.0.63 cpe:2.3:a:apache:http_server:2.0.63:*:*:*:*:*:*:*

References for CVE-2011-4317

URL Tags
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c03360041
http://kb.juniper.net/JSA10585
http://lists.apple.com/archives/security-announce/2012/Sep/msg00004.html
http://lists.opensuse.org/opensuse-updates/2013-02/msg00009.html
http://lists.opensuse.org/opensuse-updates/2013-02/msg00012.html
http://marc.info/?l=bugtraq&m=133294460209056&w=2
http://marc.info/?l=bugtraq&m=134987041210674&w=2
http://rhn.redhat.com/errata/RHSA-2012-0128.html
http://secunia.com/advisories/48551
http://support.apple.com/kb/HT5501
http://thread.gmane.org/gmane.comp.apache.devel/46440 Exploit
http://www.debian.org/security/2012/dsa-2405
http://www.mandriva.com/security/advisories?name=MDVSA-2012:003
http://www.mandriva.com/security/advisories?name=MDVSA-2013:150
http://www.oracle.com/technetwork/topics/security/cpujan2015-1972971.html
http://www.oracle.com/technetwork/topics/security/cpujul2012-392727.html
http://www.securitytracker.com/id?1026353
https://bugzilla.redhat.com/show_bug.cgi?id=756483
https://community.qualys.com/blogs/securitylabs/2011/11/23/apache-reverse-proxy-bypass-issue Exploit
https://lists.apache.org/thread.html/8d63cb8e9100f28a99429b4328e4e7cebce861d5772ac9863ba2ae6f%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/f7f95ac1cd9895db2714fa3ebaa0b94d0c6df360f742a40951384a53%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/r05b5357d1f6bd106f41541ee7d87aafe3f5ea4dc3e9bde5ce09baff8%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/r1d201e3da31a2c8aa870c8314623caef7debd74a13d0f25205e26f15%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/r476d175be0aaf4a17680ef98c5153b4d336eaef76fb2224cc94c463a%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/r57608dc51b79102f3952ae06f54d5277b649c86d6533dcd6a7d201f7%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/r75cbe9ea3e2114e4271bbeca7aff96117b50c1b6eb7c4772b0337c1f%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/r9b4b963760a3cb5a4a70c902f325c6c0337fe51d5b8570416f8f8729%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/r9ea3538f229874c80a10af473856a81fbf5f694cd7f471cc679ba70b%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/r9f93cf6dde308d42a9c807784e8102600d0397f5f834890708bf6920%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/rad01d817195e6cc871cb1d73b207ca326379a20a6e7f30febaf56d24%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/rdca61ae990660bacb682295f2a09d34612b7bb5f457577fe17f4d064%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/rf6449464fd8b7437704c55f88361b66f12d5b5f90bcce66af4be4ba9%40%3Ccvs.httpd.apache.org%3E
https://lists.apache.org/thread.html/rfbaf647d52c1cb843e726a0933f156366a806cead84fbd430951591b%40%3Ccvs.httpd.apache.org%3E
cvelogic Threat Intelligence