CVE-2021-33642 json
When a file is processed, an infinite loop occurs in next_inline() of the more_curly() function.
published 2023-01-20 3 y ago modified 2026-06-17 4 mo ago also EUVD-2021-20319
- cvss
- 5.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 13%
- public exploits
- 0
- none known
Summary
When a file is processed, an infinite loop occurs in next_inline() of the more_curly() function.
Patch / fix
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2021-33642 updated cvss 3.3
byacc: an infinite loop occurs in next_inline() of the more_curly() function
-
Red Hat Enterprise Linux 6 byaccaffected: no fix planned “Out of support scope”
-
Red Hat Enterprise Linux 7 byaccaffected: no fix available “Fix deferred”
-
Red Hat Enterprise Linux 8 byacc Red Hat Enterprise Linux 9 byaccnot affected: vulnerable code not present
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 19 mo ago
Exploit prediction
0.23% chance of exploitation in the next 30 days, higher than 13% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 5.5 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H |
| NVD | 3.1 | 5.5 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H |
| CNA | 3.1 | 5.5 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H |
Affected products
- n/a byacc
Classification
- Weakness
-
- CWE-835 Loop with Unreachable Exit Condition
References
-
gitee.com
/src-openeuler/byacc/commit/50225f48c6b53e9d7c936681a06682404cb8ec4d
permissions-required, third-party-advisory
Sources
- CVE List CVE-2021-33642
- NVD CVE-2021-33642
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.