Is CVE-2021-43313 actively exploited?

No active exploitation of CVE-2021-43313 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2021-43313 be exploited remotely?

Yes. CVE-2021-43313 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2021-43313?

CVE-2021-43313 has a CVSS score of 7.5 (HIGH).

HOME VULNERABILITIESCVE-2021-43313

HIGH

CVE-2021-43313

CWE-119Published: March 24, 2023· Updated: Jun 17, 2026

7.5

CVSS v3.1

Official 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 PackLinuxElf32::invert_pt_dynamic at p_lx_elf.cpp:1688.

NVD Source

Technical Analysis

CVE-2021-43313 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.5.

From a weakness classification perspective (CWE-119): Buffer overflow vulnerabilities can lead to arbitrary code execution or denial of service by corrupting adjacent memory.