What’s Vulnerable › Vulnerabilities

CVE-2021-33641

• Severity: high (CVSS 7.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2023-01-20 · updated 2026-06-17
• Weakness: CWE-416

Description

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

Affected products

• byacc: before 1.9.20200330; from 2.0 before 2.0.20210808 — fixed in 1.9.20200330, 2.0.20210808

How to fix

Upgrade to a fixed version: byacc 1.9.20200330, 2.0.20210808. Check the vendor advisory for mitigations.

References

• https://gitee.com/src-openeuler/byacc/commit/50225f48c6b53e9d7c936681a06682404cb8ec4d
• https://gitee.com/src-openeuler/byacc/commit/50225f48c6b53e9d7c936681a06682404cb8ec4d

Get alerted when CVE-2021-33641 or the next vulnerability affects your stack