CVE-2011-0495

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.

Published: 2011-01-20 Last update: 2026-04-29 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2011-0495 is rated Moderate Risk (59/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 4.21%). EPSS rose +3.63% over the last day, indicating growing attacker interest. Review affected assets and schedule remediation.

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

Exploit prediction scoring system (EPSS) score for CVE-2011-0495

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 2026-06-15 0.57% 4.21% +3.63%
2 2025-07-22 0.47% 0.57% +0.10%
3 2025-03-30 — 0.47% —

Full EPSS history (13 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2011-0495

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.0 2.0 MEDIUM
AV:N/AC:M/Au:S/C:P/I:P/A:P 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:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 6.8 6.4 [email protected]

Weakness enumeration for CVE-2011-0495

OS Trackers for CVE-2011-0495

vendor priority summary link
debian not yet assigned CVE-2011-0495 not yet assigned priority: Debian including 1 source packages (asterisk), 2 status rows across 2 suites (bullseye, sid): resolved 2. https://security-tracker.debian.org/tracker/CVE-2011-0495
ubuntu medium CVE-2011-0495 medium priority: Ubuntu including 1 source packages (asterisk), 7 status rows across 7 suites (dapper, hardy, karmic, lucid, maverick, natty, upstream): released 4, ignored 3. https://ubuntu.com/security/CVE-2011-0495

Affected software / configurations for CVE-2011-0495

Vendor Product Version Raw CPE
digium asterisk < c.3.6.2 cpe:2.3:a:digium:asterisk:*:*:*:*:business:*:*:*
digium asterisk >= 1.2.0, <= 1.2.40 cpe:2.3:a:digium:asterisk:*:*:*:*:*:*:*:*
digium asterisk >= 1.4.0, < 1.4.38.1 cpe:2.3:a:digium:asterisk:*:*:*:*:*:*:*:*
digium asterisk >= 1.4.39, < 1.4.39.1 cpe:2.3:a:digium:asterisk:*:*:*:*:*:*:*:*
digium asterisk >= 1.6.1, < 1.6.1.21 cpe:2.3:a:digium:asterisk:*:*:*:*:*:*:*:*
digium asterisk >= 1.6.2, < 1.6.2.15.1 cpe:2.3:a:digium:asterisk:*:*:*:*:*:*:*:*
digium asterisk >= 1.6.2.16, < 1.6.2.16.1 cpe:2.3:a:digium:asterisk:*:*:*:*:*:*:*:*
digium asterisk >= 1.8.0, < 1.8.1.2 cpe:2.3:a:digium:asterisk:*:*:*:*:*:*:*:*
digium asterisk >= 1.8.2, < 1.8.2.2 cpe:2.3:a:digium:asterisk:*:*:*:*:*:*:*:*
digium asterisknow 1.5 cpe:2.3:a:digium:asterisknow:1.5:*:*:*:*:*:*:*
fedoraproject fedora 13 cpe:2.3:o:fedoraproject:fedora:13:*:*:*:*:*:*:*
fedoraproject fedora 14 cpe:2.3:o:fedoraproject:fedora:14:*:*:*:*:*:*:*
debian debian_linux 6.0 cpe:2.3:o:debian:debian_linux:6.0:*:*:*:*:*:*:*
digium s800i_firmware 1.2.0 cpe:2.3:o:digium:s800i_firmware:1.2.0:*:*:*:*:*:*:*

References for CVE-2011-0495

URL Tags
http://downloads.asterisk.org/pub/security/AST-2011-001-1.6.2.diff Patch Vendor Advisory
http://downloads.asterisk.org/pub/security/AST-2011-001.html Vendor Advisory
http://lists.fedoraproject.org/pipermail/package-announce/2011-February/053689.html Third Party Advisory
http://lists.fedoraproject.org/pipermail/package-announce/2011-February/053713.html Third Party Advisory
http://osvdb.org/70518 Broken Link
http://secunia.com/advisories/42935 Third Party Advisory
http://secunia.com/advisories/43119 Third Party Advisory
http://secunia.com/advisories/43373 Third Party Advisory
http://www.debian.org/security/2011/dsa-2171 Third Party Advisory
http://www.securityfocus.com/archive/1/515781/100/0/threaded Third Party Advisory VDB Entry
http://www.securityfocus.com/bid/45839 Third Party Advisory VDB Entry
http://www.vupen.com/english/advisories/2011/0159 Permissions Required
http://www.vupen.com/english/advisories/2011/0281 Permissions Required
http://www.vupen.com/english/advisories/2011/0449 Permissions Required
https://exchange.xforce.ibmcloud.com/vulnerabilities/64831 Third Party Advisory VDB Entry
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