CVE-2021-24025
highpriority · track · 40EPSS 0.017 · 77 %ileEUUSEPSS · scored 2026-10-27
Due to incorrect string size calculations inside the preg_quote function, a large input string passed to the function can trigger an integer overflow leading to a heap overflow. This issue affects HHVM versions prior to 4.56.3, all versions between 4.57.0 and 4.80.1, all versions between 4.81.0 and 4.93.1, and versions 4.94.0, 4.95.0, 4.96.0, 4.97.0, 4.98.0.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.5–9.8
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (16)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (7)
External citations — patches, advisories, analysis.
- https://github.com/facebook/hhvm/commit/08193b7f0cd3910256e00d599f0f3eb2519c44cacnnvd
- https://hhvm.com/blog/2021/02/25/security-update.htmlcnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2021-24025cnnvd
- https://github.com/facebook/hhvm/commit/08193b7f0cd3910256e00d599f0f3eb2519c44caenisa_euvd
- https://hhvm.com/blog/2021/02/25/security-update.htmlenisa_euvd
- https://github.com/facebook/hhvm/commit/08193b7f0cd3910256e00d599f0f3eb2519c44caPatchThird Party Advisorynvd
- https://hhvm.com/blog/2021/02/25/security-update.htmlRelease NotesThird Party Advisorynvd
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