CVE-2011-4317
MEDIUM · CVSS 4.3EPSS 59.6%EU EUVD
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.
Key facts
- CVSS score
- 4.3 (v2.0)
- Severity
- MEDIUM
- CVSS vector
AV:N/AC:M/Au:N/C:N/I:P/A:N- Weakness (CWE)
- CWE-20
- EPSS score
- 59.6% (99th percentile)
- In CISA KEV
- No
- In EU EUVD
- Yes (EUVD-2011-4251)
- Published
- November 30, 2011
- NVD last modified
- June 16, 2026
- Status
- Modified
EU Vulnerability Database (EUVD)
This vulnerability is also tracked by ENISA as EUVD-2011-4251 in the EU Vulnerability Database. Last updated in EUVD on August 7, 2024.
View on the EU Vulnerability DatabaseAffected products
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
- apache / http server
and 50 more…
References
- 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
Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS
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