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CVE-2020-1898
The fb_unserialize function did not impose a depth limit for nested deserialization. That meant a maliciously constructed string could…
High7.5EPSS 1.2%
- Published
- Updated
- Reserved
- Assigned by
Description
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 1.2% · top 31% of all CVEs (6 Nov 2026)
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The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Weakness
Affected products
- unaffected 4.62.1 – < unspecified
- affected 4.62.0
- unaffected 4.61.1 – < unspecified
- affected 4.61.0
- unaffected 4.60.1 – < unspecified
- affected 4.60.0
- unaffected 4.59.1 – < unspecified
- affected 4.59.0
- unaffected 4.58.2 – < unspecified
- affected 4.58.0 – < unspecified
- unaffected 4.57.1 – < unspecified
- affected 4.57.0
- unaffected 4.56.1 – < unspecified
- affected 4.33.0 – < unspecified
- unaffected 4.32.3 – < unspecified
- affected unspecified – < 4.32.3
References (2)
- https://hhvm.com/blog/2020/06/30/security-update.html (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/facebook/hhvm/commit/1746dfb11fc0048366f34669e74318b8278a684c (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
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[](https://trackcve.app/cve/CVE-2020-1898)Record last updated .