Vulnerability · Published Aug 24, 2022 · Assigned by redhat
CVE-2021-4209
Medium 6.5
In plain English
A medium-severity null pointer dereference in GnuTLS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.9% (higher than 80% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS NVD)6.5Medium
Exploit odds (30 days)1.9%top 20.1% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | gnutls28 | 3.7.3-2 | DEBIAN-CVE-2021-4209 |
| Debian:13 | gnutls28 | 3.7.3-2 | DEBIAN-CVE-2021-4209 |
| Debian:14 | gnutls28 | 3.7.3-2 | DEBIAN-CVE-2021-4209 |
| Ubuntu:22.04:LTS | gnutls28 | 3.7.3-4ubuntu1.1 | USN-5550-1 |
Affected products (as reported)
Weakness: CWE-476
References
- https://gitlab.com/gnutls/gnutls/-/issues/1306 x_refsource_MISC
- https://bugzilla.redhat.com/show_bug.cgi?id=2044156 x_refsource_MISC
- https://access.redhat.com/security/cve/CVE-2021-4209 x_refsource_MISC
- https://gitlab.com/gnutls/gnutls/-/merge_requests/1503 x_refsource_MISC
- https://gitlab.com/gnutls/gnutls/-/commit/3db352734472d851318944db13be73da61300568 x_refsource_MISC
- https://security.netapp.com/advisory/ntap-20220915-0005/ x_refsource_CONFIRM
- https://cert-portal.siemens.com/productcert/html/ssa-398330.html