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CRITICAL

CVE-2021-32840

CVSS v3

9.8

CRITICAL

EPSS Score

1.9 %

exploit probability, as of 2026-10-19

CISA KEV

No

known exploited

Exploitation

—

SSVC status

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Affected and fixed versions

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • SharpZipLibNuGetall versions · fixed in 1.3.3

Full record on NVD

Description

SharpZipLib (or #ziplib) is a Zip, GZip, Tar and BZip2 library. Prior to version 1.3.3, a TAR file entry `../evil.txt` may be extracted in the parent directory of `destFolder`. This leads to arbitrary file write that may lead to code execution. The vulnerability was patched in version 1.3.3.

Technical details

Published
2022-01-26

Frequently asked questions

What is CVE-2021-32840?

SharpZipLib (or #ziplib) is a Zip, GZip, Tar and BZip2 library. Prior to version 1.3.3, a TAR file entry `../evil.txt` may be extracted in the parent directory of `destFolder`. This leads to arbitrary file write that may lead to code execution. The vulnerability was patched in version 1.3.3.

Is CVE-2021-32840 actively exploited?

Active exploitation of CVE-2021-32840 has not been confirmed. Its EPSS score was 1.9% on 2026-10-19, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-32840?

CVE-2021-32840 has a CVSS v3 base score of 9.8 (CRITICAL severity).

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