Tor 0.2.4.15-rc DNS Reply dns.c cached_resolve_add_answer denial of service

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.7	$0-$5k	0.00

Summaryinfo

A vulnerability was found in Tor 0.2.4.15-rc. It has been classified as problematic. The impacted element is the function cached_resolve_add_answer of the file dns.c of the component DNS Reply Handler. Performing a manipulation results in denial of service. Moreover, an exploit is present. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, was found in Tor 0.2.4.15-rc (Network Encryption Software). This affects the function cached_resolve_add_answer of the file dns.c of the component DNS Reply Handler. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability.

The weakness was disclosed 07/26/2013 as #9337 as confirmed ticket (Website). It is possible to read the advisory at trac.torproject.org. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details and a private exploit are known.

It is declared as proof-of-concept.

Upgrading to version 0.2.4.16-rc eliminates this vulnerability. The upgrade is hosted for download at gitweb.torproject.org. A possible mitigation has been published 3 weeks after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at OSVDB (101509†). The entries VDB-11668, VDB-11666, VDB-11665 and VDB-11664 are pretty similar. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Network Encryption Software

Name

Version

0.2.4.15-rc

License

open-source

CPE 2.3info

🔍

CPE 2.2info

🔍

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 6.7

VulDB Base Score: 7.5
VulDB Temp Score: 6.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Private
Status: Proof-of-Concept
Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: Tor 0.2.4.16-rc

Timelineinfo

07/26/2013 🔍
08/10/2013 +15 days 🔍
12/30/2013 +142 days 🔍
03/24/2019 +1910 days 🔍

Sourcesinfo

Advisory: #9337
Status: Confirmed

GCVE (VulDB): GCVE-100-11667
OSVDB: 101509

scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 12/30/2013 11:34
Updated: 03/24/2019 08:56
Changes: 12/30/2013 11:34 (50), 03/24/2019 08:56 (2)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.