CVE-2020-1898
mediumpriority · track · 30EPSS 0.012 · 68 %ileEUUSEPSS · scored 2026-10-27
The fb_unserialize function did not impose a depth limit for nested deserialization. That meant a maliciously constructed string could cause deserialization to recurse, leading to stack exhaustion. This issue affected HHVM prior to v4.32.3, between versions 4.33.0 and 4.56.0, 4.57.0, 4.58.0, 4.58.1, 4.59.0, 4.60.0, 4.61.0, 4.62.0.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (17)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
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references (7)
External citations — patches, advisories, analysis.
- https://github.com/facebook/hhvm/commit/1746dfb11fc0048366f34669e74318b8278a684ccnnvd
- https://hhvm.com/blog/2020/06/30/security-update.htmlcnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2020-1898cnnvd
- https://github.com/facebook/hhvm/commit/1746dfb11fc0048366f34669e74318b8278a684cenisa_euvd
- https://hhvm.com/blog/2020/06/30/security-update.htmlenisa_euvd
- https://github.com/facebook/hhvm/commit/1746dfb11fc0048366f34669e74318b8278a684cPatchThird Party Advisorynvd
- https://hhvm.com/blog/2020/06/30/security-update.htmlVendor Advisorynvd
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