CVE-2021-4209

Description

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.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.15%
Third-Party Advisory redhat.com Third-Party Advisory redhat.com Third-Party Advisory gitlab.com Third-Party Advisory gitlab.com Third-Party Advisory gitlab.com Third-Party Advisory netapp.com
Affected: n/a GnuTLS
Published at:
Updated at:

References

Link Tags
https://gitlab.com/gnutls/gnutls/-/issues/1306 third party advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2044156 issue tracking third party advisory
https://access.redhat.com/security/cve/CVE-2021-4209 third party advisory
https://gitlab.com/gnutls/gnutls/-/merge_requests/1503 third party advisory
https://gitlab.com/gnutls/gnutls/-/commit/3db352734472d851318944db13be73da61300568 third party advisory patch
https://security.netapp.com/advisory/ntap-20220915-0005/ third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-4209?
CVE-2021-4209 has been scored as a medium severity vulnerability.
How to fix CVE-2021-4209?
To fix CVE-2021-4209, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-4209 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-4209 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-4209?
CVE-2021-4209 affects n/a GnuTLS.
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