What’s Vulnerable › Vulnerabilities

CVE-2011-0495

• Severity: medium (CVSS 6.0 v2.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 4.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2011-01-20 · updated 2026-06-16
• Weakness: CWE-787

Description

Stack-based buffer overflow in the ast_uri_encode function in main/utils.c in Asterisk Open Source before 1.4.38.1, 1.4.39.1, 1.6.1.21, 1.6.2.15.1, 1.6.2.16.1, 1.8.1.2, 1.8.2.; and Business Edition before C.3.6.2; when running in pedantic mode allows remote authenticated users to execute arbitrary code via crafted caller ID data in vectors involving the (1) SIP channel driver, (2) URIENCODE dialplan function, or (3) AGI dialplan function.

Affected products

• Debian Linux: 6.0
• Digium Asterisk: before c.3.6.2; from 1.2.0 through 1.2.40; from 1.4.0 before 1.4.38.1; from 1.4.39 before 1.4.39.1; from 1.6.1 before 1.6.1.21; from 1.6.2 before 1.6.2.15.1 — fixed in 1.4.38.1, 1.4.39.1, 1.6.1.21, 1.6.2.15.1, 1.6.2.16.1, 1.8.1.2
• Digium Asterisknow: 1.5
• Digium S800I Firmware: 1.2.0
• Fedoraproject Fedora: 13, 14

How to fix

Upgrade to a fixed version: Digium Asterisk 1.4.38.1, 1.4.39.1, 1.6.1.21, 1.6.2.15.1. Check the vendor advisory for mitigations.

References

• http://downloads.asterisk.org/pub/security/AST-2011-001-1.6.2.diff
• http://downloads.asterisk.org/pub/security/AST-2011-001.html
• http://lists.fedoraproject.org/pipermail/package-announce/2011-February/053689.html
• http://lists.fedoraproject.org/pipermail/package-announce/2011-February/053713.html
• http://osvdb.org/70518
• http://secunia.com/advisories/42935
• http://secunia.com/advisories/43119
• http://secunia.com/advisories/43373
• http://www.debian.org/security/2011/dsa-2171
• http://www.securityfocus.com/archive/1/515781/100/0/threaded
• http://www.securityfocus.com/bid/45839
• http://www.vupen.com/english/advisories/2011/0159

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