Input validation error in tor.eff Tor

1) Input validation error

EUVDB-ID: #VU43518

Risk: Low

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2012-4922

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to perform service disruption.

The tor_timegm function in common/util.c in Tor before 0.2.2.39, and 0.2.3.x before 0.2.3.22-rc, does not properly validate time values, which allows remote attackers to cause a denial of service (assertion failure and daemon exit) via a malformed directory object, a different vulnerability than CVE-2012-4419.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Tor: 0.0.2 - 0.2.3.21

CPE2.3

• cpe:2.3:a:tor_eff_org:tor:0.0.2:*:*:*:*:*:*:*
• cpe:2.3:a:tor_eff_org:tor:0.0.3:*:*:*:*:*:*:*
• cpe:2.3:a:tor_eff_org:tor:0.0.4:*:*:*:*:*:*:*

External links

https://lists.fedoraproject.org/pipermail/package-announce/2012-September/088006.html
https://lists.opensuse.org/opensuse-updates/2012-10/msg00005.html
https://openwall.com/lists/oss-security/2012/09/12/5
https://security.gentoo.org/glsa/glsa-201301-03.xml
https://gitweb.torproject.org/tor.git/blob/release-0.2.2:/ReleaseNotes
https://gitweb.torproject.org/tor.git/commit/973c18bf0e84d14d8006a9ae97fde7f7fb97e404
https://lists.torproject.org/pipermail/tor-talk/2012-September/025501.html
https://trac.torproject.org/projects/tor/ticket/6811

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to trick the victim to visit a specially crafted website.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.