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CVE-2021-43312

Published: Mar 24, 2023Updated: Apr 11, 2025 Sources: CVE List NVDCWE-119
NVD MITRE
7.5CVSSHIGH
EPSS Score
0.8%
Top 47.7%
CISA KEV
Not in KEV
Exploits
1 Known
Remediation
Patch Available

Description

A heap-based buffer overflow was discovered in upx, during the variable 'bucket' points to an inaccessible address. The issue is being triggered in the function PackLinuxElf64::invert_pt_dynamic at p_lx_elf.cpp:5239.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
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Weaknesses

CWE-119CWE-787

Affected Products

upxupx
Library
DevTools & CI / build-test-tools
upxn/a
upxoss-projectATDevTools & CIaka ultimate packer for executables

Attack Graph

Products CVE Techniques Tactics

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

Exploitability

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://github.com/upx/upx/issues/379
github.com

Timeline

Published
Mar 24, 2023
Last Updated
Apr 11, 2025

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