Vulnerability Monitor

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CVE-2011-2516

Off-by-one error in the XML signature feature in Apache XML Security for C++ 1.6.0, as used in Shibboleth before 2.4.3 and possibly other products, allows remote attackers to cause a denial of service (crash) via a signature using a large RSA key, which triggers a buffer overflow.

Security Impact Summary

CVE-2011-2516 is a security vulnerability that . Impacting 2 products from apache, from shibboleth organizations running these solutions should prioritize assessment and patching.

Historical Context

Documented in 2011, this vulnerability occurred amid the cloud computing expansion era, where traditional network perimeter security models were being reevaluated. Organizations were transitioning from isolated infrastructure to interconnected systems, creating new attack surfaces that vulnerabilities like this could exploit.

Published

2011-07-11T20:55:01.380

Last Modified

2025-04-11T00:51:21.963

Status

Deferred

Source

[email protected]

Severity

CVSSv2: 5.0 (MEDIUM)

CVSSv2 Vector

AV:N/AC:L/Au:N/C:N/I:N/A:P

Access Vector: NETWORK
Access Complexity: LOW
Authentication: NONE
Confidentiality Impact: NONE
Integrity Impact: NONE
Availability Impact: PARTIAL

Exploitability Score

10.0

Impact Score

2.9

Weaknesses

Type: Primary
CWE-189

Affected Vendors & Products

Type	Vendor	Product	Version/Range	Vulnerable?
Application	apache	xml_security_for_c\+\+	1.6.0	Yes
Application	shibboleth	shibboleth-sp	≤ 2.4.2	Yes
Application	shibboleth	shibboleth-sp	1.3.1	Yes
Application	shibboleth	shibboleth-sp	1.3.2	Yes
Application	shibboleth	shibboleth-sp	1.3.3	Yes
Application	shibboleth	shibboleth-sp	1.3.4	Yes
Application	shibboleth	shibboleth-sp	1.3.5	Yes
Application	shibboleth	shibboleth-sp	1.3f	Yes
Application	shibboleth	shibboleth-sp	2.0	Yes
Application	shibboleth	shibboleth-sp	2.1	Yes
Application	shibboleth	shibboleth-sp	2.2	Yes
Application	shibboleth	shibboleth-sp	2.2.1	Yes
Application	shibboleth	shibboleth-sp	2.3	Yes
Application	shibboleth	shibboleth-sp	2.3.1	Yes
Application	shibboleth	shibboleth-sp	2.4	Yes
Application	shibboleth	shibboleth-sp	2.4.1	Yes

References

http://lists.fedoraproject.org/pipermail/package-announce/2011-July/063159.html ([email protected])
http://lists.fedoraproject.org/pipermail/package-announce/2011-July/063229.html ([email protected])
http://santuario.apache.org/secadv/CVE-2011-2516.txt Vendor Advisory ([email protected])
http://secunia.com/advisories/45151 Vendor Advisory ([email protected])
http://secunia.com/advisories/45191 Vendor Advisory ([email protected])
http://secunia.com/advisories/45198 ([email protected])
http://secunia.com/advisories/45491 ([email protected])
http://shibboleth.internet2.edu/secadv/secadv_20110706.txt Vendor Advisory ([email protected])
http://www.debian.org/security/2011/dsa-2277 ([email protected])
http://www.securityfocus.com/archive/1/518756/100/0/threaded ([email protected])
http://www.securityfocus.com/bid/48611 ([email protected])
http://www.securitytracker.com/id?1025755 ([email protected])
https://exchange.xforce.ibmcloud.com/vulnerabilities/68420 ([email protected])
https://issues.apache.org/jira/browse/SANTUARIO-271 Exploit ([email protected])
https://lists.apache.org/thread.html/680e6938b6412e26d5446054fd31de2011d33af11786b989127d1cc3%40%3Ccommits.santuario.apache.org%3E ([email protected])
https://lists.apache.org/thread.html/r1c07a561426ec5579073046ad7f4207cdcef452bb3100abaf908e0cd%40%3Ccommits.santuario.apache.org%3E ([email protected])
http://lists.fedoraproject.org/pipermail/package-announce/2011-July/063159.html (af854a3a-2127-422b-91ae-364da2661108)
http://lists.fedoraproject.org/pipermail/package-announce/2011-July/063229.html (af854a3a-2127-422b-91ae-364da2661108)
http://santuario.apache.org/secadv/CVE-2011-2516.txt Vendor Advisory (af854a3a-2127-422b-91ae-364da2661108)
http://secunia.com/advisories/45151 Vendor Advisory (af854a3a-2127-422b-91ae-364da2661108)
http://secunia.com/advisories/45191 Vendor Advisory (af854a3a-2127-422b-91ae-364da2661108)
http://secunia.com/advisories/45198 (af854a3a-2127-422b-91ae-364da2661108)
http://secunia.com/advisories/45491 (af854a3a-2127-422b-91ae-364da2661108)
http://shibboleth.internet2.edu/secadv/secadv_20110706.txt Vendor Advisory (af854a3a-2127-422b-91ae-364da2661108)
http://www.debian.org/security/2011/dsa-2277 (af854a3a-2127-422b-91ae-364da2661108)
http://www.securityfocus.com/archive/1/518756/100/0/threaded (af854a3a-2127-422b-91ae-364da2661108)
http://www.securityfocus.com/bid/48611 (af854a3a-2127-422b-91ae-364da2661108)
http://www.securitytracker.com/id?1025755 (af854a3a-2127-422b-91ae-364da2661108)
https://exchange.xforce.ibmcloud.com/vulnerabilities/68420 (af854a3a-2127-422b-91ae-364da2661108)
https://issues.apache.org/jira/browse/SANTUARIO-271 Exploit (af854a3a-2127-422b-91ae-364da2661108)
https://lists.apache.org/thread.html/680e6938b6412e26d5446054fd31de2011d33af11786b989127d1cc3%40%3Ccommits.santuario.apache.org%3E (af854a3a-2127-422b-91ae-364da2661108)
https://lists.apache.org/thread.html/r1c07a561426ec5579073046ad7f4207cdcef452bb3100abaf908e0cd%40%3Ccommits.santuario.apache.org%3E (af854a3a-2127-422b-91ae-364da2661108)

How SecUtils Interprets This CVE

SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For apache's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.