bzip3 up to 1.2.2/3.a libbzip3.a bz3_decode_block denial of service

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in bzip3 up to 1.2.2/3.a. Affected by this issue is the function bz3_decode_block in the library libbzip3.a. Such manipulation leads to denial of service. This vulnerability is documented as CVE-2023-29420. The attack can be executed remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in bzip3 up to 1.2.2/3.a. It has been rated as problematic. Affected by this issue is the function bz3_decode_block in the library libbzip3.a. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. CVE summarizes:

An issue was discovered in libbzip3.a in bzip3 before 1.2.3. There is a crash caused by an invalid memmove in bz3_decode_block.

The weakness was released 04/06/2023 as 92. The advisory is shared for download at github.com. This vulnerability is handled as CVE-2023-29420 since 04/06/2023. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1499.

Upgrading to version 1.2.3 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch bb06deb85f1c249838eb938e0dab271d4194f8fa is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2023-32989). Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CVSSv2info

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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: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: bzip3 1.2.3
Patch: bb06deb85f1c249838eb938e0dab271d4194f8fa

Timelineinfo

04/06/2023 🔍
04/06/2023 +0 days 🔍
04/06/2023 +0 days 🔍
12/09/2025 +978 days 🔍

Sourcesinfo

Advisory: 92
Status: Confirmed

CVE: CVE-2023-29420 (🔍)
GCVE (CVE): GCVE-0-2023-29420
GCVE (VulDB): GCVE-100-225116
EUVD: 🔍

Entryinfo

Created: 04/06/2023 13:56
Updated: 12/09/2025 18:05
Changes: 04/06/2023 13:56 (44), 04/23/2023 13:28 (11), 12/09/2025 18:05 (16)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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