bzip3 up to 1.2.2/3.a libbzip3.a bz3_decode_block out-of-bounds write

CVSS Meta Temp Score
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CTI Interest Score
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7.4$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in bzip3 up to 1.2.2/3.a. Impacted is the function bz3_decode_block in the library libbzip3.a. The manipulation results in out-of-bounds write. This vulnerability is known as CVE-2023-29421. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as critical, was found in bzip3 up to 1.2.2/3.a. Affected is the function bz3_decode_block in the library libbzip3.a. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. CWE is classifying the issue as CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

An issue was discovered in libbzip3.a in bzip3 before 1.2.3. There is an out-of-bounds write in bz3_decode_block.

The weakness was published 04/06/2023 as 94. The advisory is shared for download at github.com. This vulnerability is traded as CVE-2023-29421 since 04/06/2023. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available.

Upgrading to version 1.2.3 eliminates this vulnerability. The upgrade is hosted for download at github.com.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2023-32990). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.4

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
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

Timelineinfo

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

Sourcesinfo

Advisory: 94
Status: Confirmed

CVE: CVE-2023-29421 (🔍)
GCVE (CVE): GCVE-0-2023-29421
GCVE (VulDB): GCVE-100-225120
EUVD: 🔍

Entryinfo

Created: 04/06/2023 14:00
Updated: 12/09/2025 18:05
Changes: 04/06/2023 14:00 (42), 04/23/2023 13:40 (11), 12/09/2025 18:05 (16)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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