CVE-2021-20285

A flaw was found in upx canPack in p_lx_elf.cpp in UPX 3.96. This flaw allows attackers to cause a denial of service (SEGV or buffer overflow and application crash) or possibly have unspecified other impacts via a crafted ELF. The highest threat from this vulnerability is to system availability.

CVSS v3 6.6 MEDIUM
CVSS v2.0 8.3 HIGH

6.6^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 4.7

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

8.3^/10

CVSS v2.0 : HIGH

Vector : AV:N/AC:M/Au:N/C:P/I:P/A:C

Exploitability : 8.6 / Impact : 8.5

Access Vector NETWORK

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact COMPLETE

References

Link	Resource
https://bugzilla.redhat.com/show_bug.cgi?id=1937787	Issue Tracking Third Party Advisory
https://github.com/upx/upx/issues/421	Exploit Issue Tracking Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1937787	Issue Tracking Third Party Advisory
https://github.com/upx/upx/issues/421	Exploit Issue Tracking Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:upx:upx:3.96:*:*:*:*:*:*:*

History

11 Apr 2025, 12:27

Type	Values Removed	Values Added
CPE	cpe:2.3:a:upx_project:upx:3.96:::::::*	cpe:2.3:a:upx:upx:3.96:::::::*
First Time		Upx upx Upx

21 Nov 2024, 05:46

Type	Values Removed	Values Added
References	~~() https://bugzilla.redhat.com/show_bug.cgi?id=1937787 - Issue Tracking, Third Party Advisory~~	() https://bugzilla.redhat.com/show_bug.cgi?id=1937787 - Issue Tracking, Third Party Advisory
References	~~() https://github.com/upx/upx/issues/421 - Exploit, Issue Tracking, Third Party Advisory~~	() https://github.com/upx/upx/issues/421 - Exploit, Issue Tracking, Third Party Advisory

05 Aug 2022, 17:44

Type	Values Removed	Values Added
CWE	~~CWE-119~~	CWE-787

Information

Published : 2021-03-26 17:15

Updated : 2025-04-11 12:27

NVD link : CVE-2021-20285

Mitre link : CVE-2021-20285

CVE.ORG link : CVE-2021-20285

JSON object : View

Products Affected

upx

upx

CWE

CWE-119

Improper Restriction of Operations within the Bounds of a Memory Buffer

CWE-787

Out-of-bounds Write

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