Avast Antivirus up to 4.7.981 Zoo Archive unzoo.c denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability classified as critical was found in Avast Antivirus up to 4.7.981 (Anti-Malware Software). Affected by this vulnerability is some unknown functionality of the file unzoo.c of the component Zoo Archive Handler. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The program does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect availability. The summary by CVE is:

zoo decoder 2.10 (zoo-2.10), as used in multiple products including (1) Barracuda Spam Firewall 3.4 and later with virusdef before 2.0.6399, (2) Spam Firewall before 3.4 20070319 with virusdef before 2.0.6399o, and (3) AMaViS 2.4.1 and earlier, allows remote attackers to cause a denial of service (infinite loop) via a ZOO archive with a direntry structure that points to a previous file.

The weakness was released 05/08/2007 by Jean-Sebastien Guay-Leroux (Website). The advisory is shared at guay-leroux.com. This vulnerability is known as CVE-2007-1669 since 03/24/2007. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details and also a public exploit are known.

It is declared as proof-of-concept.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at X-Force (34080). Entries connected to this vulnerability are available at 3066, 3060, 3073 and 3090.






  • free

CPE 2.3info

CPE 2.2info


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: 🔍



VulDB Base Score: 🔍
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NVD Base Score: 🔍


Class: Denial of service
CWE: CWE-404
ATT&CK: T1499

Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍


Threat Intelligenceinfo

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


Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍


03/24/2007 🔍
05/04/2007 +40 days 🔍
05/08/2007 +4 days 🔍
05/08/2007 +0 days 🔍
05/10/2007 +2 days 🔍
05/18/2007 +8 days 🔍
03/15/2021 +5050 days 🔍


Advisory: guay-leroux.com
Researcher: Jean-Sebastien Guay-Leroux
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2007-1669 (🔍)
X-Force: 34080 - Multiple vendor ZOO archive decompression denial of service, Medium Risk
SecurityFocus: 23823
Secunia: 25122 - Barracuda Spam Firewall Zoo Denial of Service Vulnerability, Less Critical
OSVDB: 37302 - zoo Decoder unzoo.c Malformed Zoo Archive Handling DoS
Vupen: ADV-2007-1699

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


Created: 05/10/2007 02:57 PM
Updated: 03/15/2021 01:32 PM
Changes: 05/10/2007 02:57 PM (56), 08/04/2015 12:21 PM (12), 03/15/2021 01:29 PM (8), 03/15/2021 01:32 PM (2)
Complete: 🔍


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