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CVE-2011-0491

Published: Jan 19, 2011Updated: Apr 29, 2026 Sources: CVE List NVDCWE-20
NVD MITRE
5.0CVSSMEDIUM
EPSS Score
2.5%
Top 17.2%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

The tor_realloc function in Tor before 0.2.1.29 and 0.2.2.x before 0.2.2.21-alpha does not validate a certain size value during memory allocation, which might allow remote attackers to cause a denial of service (daemon crash) via unspecified vectors, related to "underflow errors."

CVSS Vector Breakdown

AV:NAC:LAu:NC:NI:NA:P
Exploitability
AV:NAccess Vector
Network
AC:LAccess Complexity
Low
Au:NAuthentication
None
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:PAvailability
Partial
Open in CVSS calculator →

Weaknesses

CWE-20

Affected Products

tortor
Mixed
Security Products / secure-gateway-vpn
n/an/a
toross-projectSecurity Productsaka tor project

Attack Graph

Products CVE Techniques Tactics

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Exploitability

Official Patch Available

MITRE ATT&CK

1 technique
Initial Access
View detailed technique mapping

References

http://archives.seul.org/or/announce/Jan-2011/msg00000.html
archives.seul.org
http://blog.torproject.org/blog/tor-02129-released-security-patches
blog.torproject.org
http://www.securityfocus.com/bid/45953
securityfocus.com
and 3 more references View all →

Timeline

Published
Jan 19, 2011
Last Updated
Apr 29, 2026

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