CVE-2021-4209
published 2022-08-24CVE-2021-4209: 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…
PriorityP431medium6.5CVSS 3.1
AVNACLPRLUINSUCNINAH
EPSS
1.38%
69.1th percentile
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
5 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | gnutls28 | < gnutls28 3.7.3-2 (bookworm) | gnutls28 3.7.3-2 (bookworm) |
| gnu | gnutls | < 3.7.3 | 3.7.3 |
| gnu | gnutls | — | — |
| msrc | cm1_gnutls_3.6.14-7_on_cbl_mariner_1.0 | — | — |
| redhat | enterprise_linux | — | — |
CVSS provenance
nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv6.5MEDIUM
vendor_debian6.5MEDIUM
vendor_msrc6.5MEDIUM
vendor_redhat6.5MEDIUM
vendor_ubuntu6.5MEDIUM
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GHSA
GHSA-xj78-h3gx-cm6v: A NULL pointer dereference flaw was found in GnuTLS
ghsa_unreviewed·2022-08-25
CVE-2021-4209 [MEDIUM] CWE-476 GHSA-xj78-h3gx-cm6v: A NULL pointer dereference flaw was found in GnuTLS
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.
OSV
CVE-2021-4209: A NULL pointer dereference flaw was found in GnuTLS
osv·2022-08-24·CVSS 6.5
CVE-2021-4209 [MEDIUM] CVE-2021-4209: A NULL pointer dereference flaw was found in GnuTLS
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.
OSV
gnutls28 vulnerabilities
osv·2022-08-04·CVSS 6.5
CVE-2021-4209 [MEDIUM] gnutls28 vulnerabilities
gnutls28 vulnerabilities
It was discovered that GnuTLS incorrectly handled certain memory
operations. A remote attacker could possibly use this issue to cause GnuTLS
to crash, resulting in a denial of service. This issue only affected Ubuntu
18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2021-4209)
It was discovered that GnuTLS incorrectly handled the verification of
certain pkcs7 signatures. A remote attacker could use this issue to cause
GnuTLS to crash, resulting in a denial of service, or possibly execute
arbitrary code. (CVE-2022-2509)
CISA ICS
Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1
cisa_ics·2023-12-14
Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1
ICS Advisory
##
Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1
Release DateDecember 14, 2023
Alert CodeICSA-23-348-10
As of January 10, 2023, CISA will no longer be updating ICS security advisories for Siemens product vulnerabilities beyond the initial advisory. For the most up-to-date information on vulnerabilities in this advisory, please see Siemens' ProductCERT Security Advisories (CERT Services | Services | Siemens Global).
View CSAF
## 1. EXECUTIVE SUMMARY
- CVSS v3 9.8
- ATTENTION: Exploitable remotely/low attack complexity
- Vendor: Siemens
- Equipment: SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1
- Vulnerabilities: Improper Restriction of XML External Entity Reference, Time-of-check Time-of-use (TOCTOU) Race Condition, Command Injection, Miss
Ubuntu
GnuTLS vulnerability
vendor_ubuntu·2022-11-30
CVE-2021-4209 GnuTLS vulnerability
Title: GnuTLS vulnerability
Summary: GnuTLS could be made to crash if it received specially crafted network
traffic from an authenticated client.
It was discovered that GnuTLS incorrectly handled certain memory
operations. A remote attacker could possibly use this issue to cause GnuTLS
to crash, resulting in a denial of service.
Instructions: In general, a standard system update will make all the necessary changes.
Microsoft
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 s
vendor_msrc·2022-08-09·CVSS 6.5
CVE-2021-4209 [MEDIUM] CWE-476 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 s
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.
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to add
Ubuntu
GnuTLS vulnerabilities
vendor_ubuntu·2022-08-04·CVSS 6.5
CVE-2021-4209 [MEDIUM] GnuTLS vulnerabilities
Title: GnuTLS vulnerabilities
Summary: Several security issues were fixed in GnuTLS.
It was discovered that GnuTLS incorrectly handled certain memory
operations. A remote attacker could possibly use this issue to cause GnuTLS
to crash, resulting in a denial of service. This issue only affected Ubuntu
18.04 LTS, and Ubuntu 20.04 LTS. (CVE-2021-4209)
It was discovered that GnuTLS incorrectly handled the verification of
certain pkcs7 signatures. A remote attacker could use this issue to cause
GnuTLS to crash, resulting in a denial of service, or possibly execute
arbitrary code. (CVE-2022-2509)
Instructions: In general, a standard system update will make all the necessary changes.
Red Hat
GnuTLS: Null pointer dereference in MD_UPDATE
vendor_redhat·2021-12-22·CVSS 6.5
CVE-2021-4209 [MEDIUM] CWE-476 GnuTLS: Null pointer dereference in MD_UPDATE
GnuTLS: Null pointer dereference in MD_UPDATE
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.
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.
Statement: This issue is classified as low severity because it requires a very specific and rare set of conditions to be triggered. The vulnerability occurs only when GnuTLS is built with Guile support disabled and when an empty input (zero-length
Debian
CVE-2021-4209: gnutls28 - A NULL pointer dereference flaw was found in GnuTLS. As Nettle's hash update fun...
vendor_debian·2021·CVSS 6.5
CVE-2021-4209 [MEDIUM] CVE-2021-4209: gnutls28 - A NULL pointer dereference flaw was found in GnuTLS. As Nettle's hash update fun...
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.
Scope: local
bookworm: resolved (fixed in 3.7.3-2)
bullseye: resolved (fixed in 3.7.1-5+deb11u1)
forky: resolved (fixed in 3.7.3-2)
sid: resolved (fixed in 3.7.3-2)
trixie: resolved (fixed in 3.7.3-2)
No detection rules found.
No public exploits indexed.
https://access.redhat.com/security/cve/CVE-2021-4209https://bugzilla.redhat.com/show_bug.cgi?id=2044156https://gitlab.com/gnutls/gnutls/-/commit/3db352734472d851318944db13be73da61300568https://gitlab.com/gnutls/gnutls/-/issues/1306https://gitlab.com/gnutls/gnutls/-/merge_requests/1503https://security.netapp.com/advisory/ntap-20220915-0005/https://access.redhat.com/security/cve/CVE-2021-4209https://bugzilla.redhat.com/show_bug.cgi?id=2044156https://gitlab.com/gnutls/gnutls/-/commit/3db352734472d851318944db13be73da61300568https://gitlab.com/gnutls/gnutls/-/issues/1306https://gitlab.com/gnutls/gnutls/-/merge_requests/1503https://security.netapp.com/advisory/ntap-20220915-0005/
2022-08-24
Published