CVE-2021-3449: NULL pointer deref in signature_algorithms processing

Severity: medium (CVSS 5.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 63.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-03-25 · updated 2026-10-08
Weakness: CWE-476

Description

An OpenSSL TLS server may crash if sent a maliciously crafted renegotiation ClientHello message from a client. If a TLSv1.2 renegotiation ClientHello omits the signature_algorithms extension (where it was present in the initial ClientHello), but includes a signature_algorithms_cert extension then a NULL pointer dereference will result, leading to a crash and a denial of service attack. A server is only vulnerable if it has TLSv1.2 and renegotiation enabled (which is the default configuration). OpenSSL TLS clients are not impacted by this issue. All OpenSSL 1.1.1 versions are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1k. OpenSSL 1.0.2 is not impacted by this issue. Fixed in OpenSSL 1.1.1k (Affected 1.1.1-1.1.1j).

Affected products

checkpoint Multi-Domain Management Firmware: r80.40, r81
Check Point Quantum Security Gateway: r80.40, r81
checkpoint Quantum Security Management Firmware: r80.40, r81
Debian Linux: 9.0, 10.0
Fedoraproject Fedora: 34
FreeBSD: 12.2, 12.2-p1, 12.2-p2
McAfee Web Gateway (MWG): 8.2.19, 9.2.10, 10.1.1
McAfee Web Gateway Cloud Service: 8.2.19, 9.2.10, 10.1.1
Active IQ Unified Manager for VMware vSphere, Linux, and Microsoft Windows: all versions
NetApp Cloud Volumes Ontap Mediator: all versions
NetApp E-Series Performance Analyzer: all versions
OnCommand Insight: all versions
NetApp OnCommand Workflow Automation: all versions
NetApp ONTAP Select Deploy administration utility: all versions
NetApp Santricity Smi-S Provider: all versions
NetApp SnapCenter: all versions
NetApp StorageGRID: all versions
Node.js: from 10.0.0 through 10.12.0; from 10.13.0 through 10.24.0; from 12.0.0 through 12.12.0; from 12.13.0 before 12.22.1; from 14.0.0 through 14.14.0; from 14.15.0 before 14.16.1 — fixed in 12.22.1, 14.16.1, 15.14.0
OpenSSL: from 1.1.1 before 1.1.1k — fixed in 1.1.1k
Oracle Communications Communications Policy Management: 12.6.0.0.0
Oracle Enterprise Manager For Storage Management: 13.4.0.0
Oracle Corporation Oracle Essbase: 21.2
Oracle Corporation GraalVM Enterprise Edition: 19.3.5, 20.3.1.2, 21.0.0.2
Oracle Corporation JD Edwards EnterpriseOne Tools: before 9.2.6.0 — fixed in 9.2.6.0
Oracle Jd Edwards World Security: a9.4
Oracle Mysql Connectors: through 8.0.23
MySQL Server: through 5.7.33; from 8.0.15 through 8.0.23
Oracle Corporation MySQL Workbench: through 8.0.23
Oracle Corporation PeopleSoft Enterprise PT PeopleTools: 8.57, 8.58, 8.59
Oracle Corporation Primavera Unifier: from 17.7 through 17.12; 19.12, 20.12, 21.12

How to fix

Upgrade to a fixed version: Node.js 12.22.1, 14.16.1, 15.14.0; OpenSSL 1.1.1k; Oracle Corporation JD Edwards EnterpriseOne Tools 9.2.6.0; Oracle Corporation Oracle Secure Backup 18.1.0.1.0; Siemens Scalance Xb-200 Firmware 4.3; Siemens Scalance Xc-200 Firmware 4.3; Siemens Scalance Xf-200Ba Firmware 4.3; Siemens Scalance Xm-400 Firmware 6.4; Siemens Scalance Xp-200 Firmware 4.3; Siemens Scalance Xr-300Wg Firmware 4.3; Siemens Scalance Xr524-8C Firmware 6.4; Siemens Scalance Xr526-8C Firmware 6.4. Check the vendor advisory for mitigations.

References

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