openEuler byacc malloc use after free

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.
6.5$0-$5k0.00

Summaryinfo

A vulnerability has been found in openEuler byacc and classified as problematic. Impacted is the function malloc. This manipulation causes use after free. This vulnerability appears as CVE-2021-33641. There is no available exploit. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability was found in openEuler byacc (the affected version unknown). It has been declared as problematic. Affected by this vulnerability is the function malloc. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

When processing files, malloc stores the data of the current line. When processing comments, malloc incorrectly accesses the released memory (use after free).

The weakness was presented 01/21/2023 as 50225f48c6b53e9d7c936681a06682404cb8ec4d. It is possible to read the advisory at gitee.com. This vulnerability is known as CVE-2021-33641 since 05/28/2021. Technical details of the vulnerability are known, but there is no available exploit.

Applying the patch 50225f48c6b53e9d7c936681a06682404cb8ec4d is able to eliminate this problem. The bugfix is ready for download at gitee.com.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.6
VulDB Meta Temp Score: 6.5

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

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

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: 50225f48c6b53e9d7c936681a06682404cb8ec4d

Timelineinfo

05/28/2021 🔍
01/21/2023 +603 days 🔍
01/21/2023 +0 days 🔍
04/04/2025 +804 days 🔍

Sourcesinfo

Advisory: 50225f48c6b53e9d7c936681a06682404cb8ec4d
Status: Confirmed

CVE: CVE-2021-33641 (🔍)
GCVE (CVE): GCVE-0-2021-33641
GCVE (VulDB): GCVE-100-219103

Entryinfo

Created: 01/21/2023 09:38
Updated: 04/04/2025 07:00
Changes: 01/21/2023 09:38 (40), 02/18/2023 08:43 (11), 04/04/2025 07:00 (21)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Interested in the pricing of exploits?

See the underground prices here!