High severity · published Apr 9, 2021
CVE-2021-29221
A local privilege escalation vulnerability was discovered in Erlang/OTP prior to version 23.2.3
7.0
CVSS
0.6%
EPSS
No
On KEV
Description
A local privilege escalation vulnerability was discovered in Erlang/OTP prior to version 23.2.3. By adding files to an existing installation's directory, a local attacker could hijack accounts of other users running Erlang programs or possibly coerce a service running with "erlsrv.exe" to execute arbitrary code as Local System. This can occur only under specific conditions on Windows with unsafe filesystem permissions.
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
High
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 48% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ER
Erlang/otp · Erlang
before 23.2.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-29221
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-29221
Exploit
https://deepsurface.com/deepsurface-security-advisory-local-privilege-escalation-in-erlang-on-windows-cve-2021-29221/
Third Party Advisory
https://github.com/erlang/otp/releases/tag/OTP-23.2.3
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