Is CVE-2021-36976 actively exploited?

CVE-2021-36976 has no public evidence of in-the-wild exploitation as of 2025-11-03.

What is the CVSS score for CVE-2021-36976?

CVE-2021-36976 has a CVSS score of 6.5 (MEDIUM severity). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

How do I patch CVE-2021-36976?

Patch guidance is available from libarchive security advisories. CVEDatabase generates AI-assisted remediation guidance on demand for CVE-2021-36976.

CVE-2021-36976 - remediation guidance & executive summary

Q: Which products are affected by CVE-2021-36976?

9 products: libarchive libarchive, fedoraproject fedora, apple ipados, apple iphone os, apple macos, and 4 more.

Description

libarchive 3.4.1 through 3.5.1 has a use-after-free in copy_string (called from do_uncompress_block and process_block).

CVSS Metrics

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Attack Vector: network
Complexity: low
Privileges: none
User Action: required
Scope: unchanged
Confidentiality: none
Integrity: none
Availability: high
Weaknesses: CWE-416 · Use After Free

Metadata

Primary Vendor: LIBARCHIVE
Published: 7/20/2021
Last Modified: 11/3/2025
Source: NIST NVD
Note: Verify all details with official vendor sources before applying patches.

Affected Products

libarchive : libarchivefedoraproject : fedoraapple : ipadosapple : iphone_osapple : macosapple : watchossplunk : universal_forwardersplunk : universal_forwardersplunk : universal_forwarder

Remediation Guidance

Executive Summary

View on NIST NVD