What is CVE-2021-33453?

CVE-2021-33453 is a high-severity vulnerability in Long Range Zip Project, classified under Use After Free. CVSS score: 7.8/10. Published 2022-07-26.

How severe is CVE-2021-33453?

High severity. CVSS v3 base score is 7.8 out of 10.

Use After Free in Long Range Zip Project

CVE-2021-33453

An issue was discovered in lrzip version 0.641. There is a use-after-free in ucompthread() in stream.c:1538.

Vulnerability class: Use-After-Free

Published 2022-07-26 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.004 (26.3th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 26th percentile — 26.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000

Affected products

Long Range Zip Project — versions 0.641

Weakness classification (CWE)

CWE-416 — Use After Free

References

github.com/ckolivas/lrzip/issues/199 (Exploit, Third Party Advisory, Issue Tracking)
gist.github.com/Clingto/bb632c0c463f4b2c97e4f65f751c5e6d (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2021-33453?: CVE-2021-33453 is a high-severity vulnerability in Long Range Zip Project, classified under Use After Free. CVSS score: 7.8/10. Published 2022-07-26.
How severe is CVE-2021-33453?: High severity. CVSS v3 base score is 7.8 out of 10.