High severity · published Mar 10, 2021
CVE-2020-1921
In the crypt function, we attempt to null terminate a buffer using the size of the input salt without validating that the offset is within the buffer
7.5
CVSS
1.2%
EPSS
No
On KEV
Description
In the crypt function, we attempt to null terminate a buffer using the size of the input salt without validating that the offset is within the buffer. 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 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 4.56.3; 4.57.0 before 4.80.2; 4.81.0 before 4.93.2; 4.94.0; 4.95.0; 4.96.0; +2 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-1921
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-1921
Patch
https://github.com/facebook/hhvm/commit/08193b7f0cd3910256e00d599f0f3eb2519c44ca
Vendor Advisory
https://hhvm.com/blog/2021/02/25/security-update.html
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