CVE-2021-20285

6.6 mediumEPSS 0.8%

Medium (6.6) in upx upx. EPSS 0.8% chance of exploitation in the next 30 days.

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.

Severity

CVSS 3.1

6.6 medium

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H

EPSS: 0.8% chance of exploitation in the next 30 days; higher than 55% of CVEs (scores of 2026-10-31)
CWEs: CWE-787, CWE-119
Published: 2021-03-26
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

upx:upx

References

https://bugzilla.redhat.com/show_bug.cgi?id=1937787
https://github.com/upx/upx/issues/421
https://bugzilla.redhat.com/show_bug.cgi?id=1937787
https://github.com/upx/upx/issues/421

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