High severity · published Mar 11, 2021
CVE-2020-1898
The fb_unserialize function did not impose a depth limit for nested deserialization
7.5
CVSS
1.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.2% · higher than 68% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HH
Hhvm · Facebook
before 4.32.3; 4.33.0 before 4.56.1; 4.57.0; 4.58.0; 4.58.1; 4.59.0; +3 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-1898
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-1898
Patch
https://github.com/facebook/hhvm/commit/1746dfb11fc0048366f34669e74318b8278a684c
Vendor Advisory
https://hhvm.com/blog/2020/06/30/security-update.html
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