What’s Vulnerable › Vulnerabilities

CVE-2020-27788

• Severity: medium (CVSS 5.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2022-08-18 · updated 2026-06-17
• Weakness: CWE-125

Description

An out-of-bounds read access vulnerability was discovered in UPX in PackLinuxElf64::canPack() function of p_lx_elf.cpp file. An attacker with a crafted input file could trigger this issue that could cause a crash leading to a denial of service.

Affected products

• upx: before 3.96 — fixed in 3.96

How to fix

Upgrade to a fixed version: upx 3.96. Check the vendor advisory for mitigations.

References

• https://github.com/upx/upx/commit/1bb93d4fce9f1d764ba57bf5ac154af515b3fc83
• https://github.com/upx/upx/issues/332
• https://github.com/upx/upx/commit/1bb93d4fce9f1d764ba57bf5ac154af515b3fc83
• https://github.com/upx/upx/issues/332

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