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CVE-2021-36770

Published: Aug 11, 2021Updated: Nov 3, 2025 Sources: CVE List NVD BDUCWE-427
NVD MITRE
7.8CVSSHIGH
EPSS Score
1.4%
Top 31.1%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

Encode.pm, as distributed in Perl through 5.34.0, allows local users to gain privileges via a Trojan horse Encode::ConfigLocal library (in the current working directory) that preempts dynamic module loading. Exploitation requires an unusual configuration, and certain 2021 versions of Encode.pm (3.05 through 3.11). This issue occurs because the || operator evaluates @INC in a scalar context, and thus @INC has only an integer value.

CVSS Vector Breakdown

AV:LAC:LPR:NUI:RS:UC:HI:HA:H
Exploitability
AV:LAttack Vector
Local
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:RUser Interaction
Required
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-427

Affected Products

Debian GNU/LinuxСообщество свободного программного обеспечения
On-premOS
Operating Systems / linux-distro
FedoraFedora Project
On-premOS
Operating Systems / linux-distro
UbuntuCanonical Ltd.
On-premOS
Operating Systems / linux-distro
p5-encodeСообщество свободного программного обеспечения
On-prem
Operating Systems / linux-distro
PerlСообщество свободного программного обеспечения
On-premLibrary
OSS Libraries / generic-library
сообщество свободного программного обеспеченияoss-projectOperating Systemsaka сообщество свободного программного обеспечения, fsf
fedora projectoss-projectUSOperating Systemsaka fedora
canonical ltd.commercialGBOperating Systemsaka canonical
and 5 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

MITRE ATT&CK

1 technique
Persistence
View detailed technique mapping

References

https://access.redhat.com/security/cve/cve-2021-36770
access.redhat.com
https://github.com/Perl/perl5/commit/c1a937fef07c061600a0078f4cb53fe9c2136bb9
github.com
https://github.com/dankogai/p5-encode/commit/527e482dc70b035d0df4f8c77a00d81f8d775c74
github.com
and 14 more references View all →

Timeline

Published
Aug 11, 2021
Last Updated
Nov 3, 2025

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