What’s Vulnerable › Vulnerabilities

CVE-2021-3700

• Severity: medium (CVSS 6.4 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: none known
• Published: 2022-02-24 · updated 2026-06-17
• Weakness: CWE-416

Description

A use-after-free vulnerability was found in usbredir in versions prior to 0.11.0 in the usbredirparser_serialize() in usbredirparser/usbredirparser.c. This issue occurs when serializing large amounts of buffered write data in the case of a slow or blocked destination.

Affected products

• Debian Linux: 9.0
• Fedoraproject Fedora: 34
• Red Hat Enterprise Linux: 6.0, 7.0, 8.0
• Spice-Space Usbredir: before 0.11.0 — fixed in 0.11.0

How to fix

Upgrade to a fixed version: Spice-Space Usbredir 0.11.0. Check the vendor advisory for mitigations.

References

• https://bugzilla.redhat.com/show_bug.cgi?id=1992830
• https://gitlab.freedesktop.org/spice/usbredir/-/commit/03c519ff5831ba
• https://lists.debian.org/debian-lts-announce/2022/03/msg00030.html
• https://bugzilla.redhat.com/show_bug.cgi?id=1992830
• https://gitlab.freedesktop.org/spice/usbredir/-/commit/03c519ff5831ba
• https://lists.debian.org/debian-lts-announce/2022/03/msg00030.html

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