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CVE-2021-4209

MEDIUM severity · CVSS 6.5 · CWE-476
6.5CVSS MEDIUM

Summary

A NULL pointer dereference flaw was found in GnuTLS. As Nettle's hash update functions internally call memcpy, providing zero-length input may cause undefined behavior. This flaw leads to a denial of service after authentication in rare circumstances.

Impact & exploitability

Attack vectorNetwork
Attack complexityLow
Privileges requiredLow
User interactionNone
Confidentiality impactNone
Integrity impactNone
Availability impactHigh
Exploit probability (EPSS)1%

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected products we track (1)

Recommendation

Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.

Official patch: https://gitlab.com/gnutls/gnutls/-/commit/3db352734472d851318944db13be73da61300568 ↗