Squid url_regex ACL bypass
| squid-urlregex-acl-bypass (15366) |  Medium Risk |
Description:
Squid Web Proxy Cache could allow a remote attacker to bypass Access Control Lists (ACL). By sending a specially-crafted URL request containing '%00', the url_regex ACL may not properly detect the malicious URL, allowing the attacker to bypass the ACL.
Platforms Affected:
- Conectiva, Linux 8.0
- Conectiva, Linux 9.0
- Debian, Debian Linux 3.0
- Gentoo, Linux
- MandrakeSoft, Mandrake Linux 10.0 AMD64
- MandrakeSoft, Mandrake Linux 10.0
- MandrakeSoft, Mandrake Linux 9.1 PPC
- MandrakeSoft, Mandrake Linux 9.1
- MandrakeSoft, Mandrake Linux 9.2 AMD64
- MandrakeSoft, Mandrake Linux 9.2
- MandrakeSoft, Mandrake Linux Corporate Server 2.1 X86_64
- MandrakeSoft, Mandrake Linux Corporate Server 2.1
- MandrakeSoft, Mandrake Multi Network Firewall 8.2
- OpenPKG, OpenPKG 1.3
- OpenPKG, OpenPKG 2.0
- OpenPKG, OpenPKG CURRENT
- RedHat, Enterprise Linux 2.1 AS
- RedHat, Enterprise Linux 2.1 ES
- RedHat, Enterprise Linux 3 AS
- RedHat, Enterprise Linux 3 WS
- RedHat, Enterprise Linux 3 ES
- RedHat, Linux 9.0
- RedHat, Linux Advanced Workstation 2.1 Itanium
- SCO, SCO OpenServer 5.0.6
- SCO, SCO OpenServer 5.0.7
- SCO, SCO UnixWare 7.1.4
- Squid-Cache, Squid 2.0.PATCH2
- Squid-Cache, Squid 2.1.PATCH2
- Squid-Cache, Squid 2.3.STABLE4
- Squid-Cache, Squid 2.3.STABLE5
- Squid-Cache, Squid 2.4
- Squid-Cache, Squid 2.4.STABLE2
- Squid-Cache, Squid 2.4.STABLE6
- Squid-Cache, Squid 2.4.STABLE7
- Squid-Cache, Squid 2.5.STABLE1
- Squid-Cache, Squid 2.5.STABLE3
- Squid-Cache, Squid 2.5.STABLE4
- Turbolinux, Turbolinux 7 Server
- Turbolinux, Turbolinux 7 Workstation
- Turbolinux, Turbolinux 8 Server
- Turbolinux, Turbolinux 8 Workstation
- Turbolinux, Turbolinux Appliance Server 1.0
- Turbolinux, Turbolinux Appliance Server 1.0 Hosting Ed
- Turbolinux, Turbolinux Appliance Server 1.0 Workgroup Ed
Remedy:
Upgrade to the latest version of Squid (2.5.stable5 or later), available from the Squid Web site. See References.
For Red Hat Linux 9:
Upgrade to the latest version of squid (2.5.STABLE1-3.9 or later), as listed in RHSA-2004:134-01. See References.
For Debian/GNU Linux 3.0 (woody):
Upgrade to the lastest version of squid (2.4.6-2woody2 or later), as listed in DSA-474-1. See References.
For Conectiva Linux:
Upgrade to the latest squid package, as listed below. Refer to Conectiva Linux Security Announcement CLSA-2004:838. See References.
Conectiva Linux 8: 2.4.7-1U80_4cl or later
Conectiva Linux 9: 2.5.5-25761U90_3cl or later
For SCO OpenServer 5.0.6, and 5.0.7:
Upgrade to the appropriate fixed binaries, as listed in SCO Security Advisory SCOSA-2004.13. See References.
For SCO UnixWare 7.1.4:
Upgrade to the appropriate fixed binaries, as listed in SCO Security Advisory SCOSA-2005.16. See References.
For Turbolinux:
Upgrade to the latest squid package, as listed below. Refer to Turbolinux Security Advisory TLSA-2004-24 for more information. See References.
Turbolinux Appliance Server 1.0 Hosting Edition: 2.5.STABLE6-9 or later
Turbolinux 8 Server and Workstation: 2.5.STABLE6-7or later
Turbolinux 7 Server and Workstation: 2.5.STABLE6-7 or later
For OpenPKG:
Refer to OpenPKG Security Advisory OpenPKG-SA-2004.008 for patch, upgrade, or suggested workaround information. See References.
For other distributions:
Contact your vendor for upgrade or patch information.
Consequences:
Bypass Security
References:
- CIAC Information Bulletin O-108, Squid ACL Bypass Vulnerability at http://www.ciac.org/ciac/bulletins/o-108.shtml.
- Conectiva Linux Security Announcement CLSA-2004:838, ACL bypass vulnerability at http://distro.conectiva.com/atualizacoes/index.php?id=a&anuncio=000838.
- SCO Security Advisory SCOSA-2004.13, squid %-encoded characters in a URL at http://www.linuxsecurity.com/content/view/106408/98/.
- SCO Security Advisory SCOSA-2005.16, UnixWare 7.1.4 : squid updated package fixes several security issues at http://www.linuxsecurity.com/content/view/106408/98/.
- Squid Proxy Cache Security Update Advisory SQUID-2004:1, Squid-2.5.STABLE5 fixes and features for URL encoding tricks. at http://www.squid-cache.org/Advisories/SQUID-2004_1.txt.
- Squid Web site, Squid Web Proxy Cache at http://www.squid-cache.org/.
- BID-9778: Squid Proxy NULL URL Character Unauthorized Access Vulnerability
- CVE-2004-0189: The %xx URL decoding function in Squid 2.5STABLE4 and earlier allows remote attackers to bypass url_regex ACLs via a URL with a NULL (%00) characterm, which causes Squid to use only a portion of the requested URL when comparing it against the access control lists.
- DSA-474: squid -- ACL bypass
- GLSA-200403-11: Squid ACL [url_regex] bypass vulnerability
- MDKSA-2004:025: Updated squid packages fix vulnerability
- OpenPKG-SA-2004.008: Squid
- OSVDB ID: 5916: Squid Proxy %xx URL Encoding ACL Bypass
- RHSA-2004-133: squid security update
- RHSA-2004-134: Updated squid package fixes security vulnerability
Reported:
Mar 01, 2004
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