CA certificate check bypass with X509_V_FLAG_X509_STRICT

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Summary

CVECVE-2021-3450
StatePUBLISHED
Assigneropenssl
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-03-25 15:15:13 UTC
Updated2026-10-08 21:17:40 UTC
DescriptionThe X509_V_FLAG_X509_STRICT flag enables additional security checks of the certificates present in a certificate chain. It is not set by default. Starting from OpenSSL version 1.1.1h a check to disallow certificates in the chain that have explicitly encoded elliptic curve parameters was added as an additional strict check. An error in the implementation of this check meant that the result of a previous check to confirm that certificates in the chain are valid CA certificates was overwritten. This effectively bypasses the check that non-CA certificates must not be able to issue other certificates. If a "purpose" has been configured then there is a subsequent opportunity for checks that the certificate is a valid CA. All of the named "purpose" values implemented in libcrypto perform this check. Therefore, where a purpose is set the certificate chain will still be rejected even when the strict flag has been used. A purpose is set by default in libssl client and server certificate verification routines, but it can be overridden or removed by an application. In order to be affected, an application must explicitly set the X509_V_FLAG_X509_STRICT verification flag and either not set a purpose for the certificate verification or, in the case of TLS client or server applications, override the default purpose. OpenSSL versions 1.1.1h and newer 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 1.1.1h-1.1.1j).

Risk And Classification

Primary CVSS: v3.1 7.4 HIGH from [email protected]

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

Problem Types: CWE-295 | Invalid Certificate Verification

VersionSourceTypeScoreSeverityVector
3.1[email protected]Primary7.4HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
2.0[email protected]Primary5.8AV:N/AC:M/Au:N/C:P/I:P/A:N

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

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

CVSS v2.0 Breakdown

Access Vector
Network
Access Complexity
Medium
Authentication
None
Confidentiality
Partial
Integrity
Partial
Availability
None

AV:N/AC:M/Au:N/C:P/I:P/A:N

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Operating System Fedoraproject Fedora 34 All All All
Operating System Freebsd Freebsd 12.2 - All All
Operating System Freebsd Freebsd 12.2 p1 All All
Operating System Freebsd Freebsd 12.2 p2 All All
Application Mcafee Web Gateway 10.1.1 All All All
Application Mcafee Web Gateway 8.2.19 All All All
Application Mcafee Web Gateway 9.2.10 All All All
Application Mcafee Web Gateway Cloud Service 10.1.1 All All All
Application Mcafee Web Gateway Cloud Service 8.2.19 All All All
Application Mcafee Web Gateway Cloud Service 9.2.10 All All All
Application Netapp Cloud Volumes Ontap Mediator - All All All
Application Netapp Oncommand Workflow Automation - All All All
Application Netapp Ontap Select Deploy Administration Utility - All All All
Hardware Netapp Santricity Smi-s Provider - All All All
Operating System Netapp Santricity Smi-s Provider Firmware - All All All
Hardware Netapp Storagegrid - All All All
Application Netapp Storagegrid - All All All
Operating System Netapp Storagegrid Firmware - All All All
Application Nodejs Node.js All All All All
Application Openssl Openssl All All All All
Application Oracle Commerce Guided Search 11.3.2 All All All
Application Oracle Enterprise Manager For Storage Management 13.4.0.0 All All All
Application Oracle Graalvm 19.3.5 All All All
Application Oracle Graalvm 20.3.1.2 All All All
Application Oracle Graalvm 21.0.0.2 All All All
Application Oracle Jd Edwards Enterpriseone Tools All All All All
Application Oracle Jd Edwards World Security a9.4 All All All
Application Oracle Mysql Connectors All All All All
Application Oracle Mysql Enterprise Monitor All All All All
Application Oracle Mysql Server All All All All
Application Oracle Mysql Server All All All All
Application Oracle Mysql Workbench All All All All
Application Oracle Peoplesoft Enterprise Peopletools All All All All
Application Oracle Secure Backup All All All All
Application Oracle Secure Global Desktop 5.6 All All All
Application Oracle Weblogic Server 12.2.1.4.0 All All All
Application Oracle Weblogic Server 14.1.1.0.0 All All All
Application Sonicwall Capture Client All All All All
Application Sonicwall Email Security All All All All
Hardware Sonicwall Sma100 - All All All
Operating System Sonicwall Sma100 Firmware All All All All
Operating System Sonicwall Sonicos All All All All
Application Tenable Nessus All All All All
Application Tenable Nessus Agent All All All All
Application Tenable Nessus Network Monitor 5.11.0 All All All
Application Tenable Nessus Network Monitor 5.11.1 All All All
Application Tenable Nessus Network Monitor 5.12.0 All All All
Application Tenable Nessus Network Monitor 5.12.1 All All All
Application Tenable Nessus Network Monitor 5.13.0 All All All
Operating System Windriver Linux - All All All
Operating System Windriver Linux 17.0 All All All
Operating System Windriver Linux 18.0 All All All
Operating System Windriver Linux 19.0 All All All

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA OpenSSL OpenSSL affected Fixed in OpenSSL 1.1.1k (Affected 1.1.1h-1.1.1j) Not specified

References

ReferenceSourceLinkTags
[SECURITY] Fedora 34 Update: openssl-1.1.1k-1.fc34 - package-announce - Fedora Mailing-Lists af854a3a-2127-422b-91ae-364da2661108 lists.fedoraproject.org
Security Advisory af854a3a-2127-422b-91ae-364da2661108 psirt.global.sonicwall.com Third Party Advisory
oss-security - Re: OpenSSL 1.1.1 CVE-2021-3450 CA certificate check bypass with X509_V_FLAG_X509_STRICT, CVE-2021-3449 NULL pointer deref in signature_algorithms processing af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List, Third Party Advisory
Multiple Vulnerabilities in OpenSSL Affecting Cisco Products: March 2021 af854a3a-2127-422b-91ae-364da2661108 tools.cisco.com Third Party Advisory
Oracle Critical Patch Update Advisory - April 2022 af854a3a-2127-422b-91ae-364da2661108 www.oracle.com Patch, Third Party Advisory
Oracle Critical Patch Update Advisory - October 2021 af854a3a-2127-422b-91ae-364da2661108 www.oracle.com Patch, Third Party Advisory
oss-security - Re: OpenSSL 1.1.1 CVE-2021-3450 CA certificate check bypass with X509_V_FLAG_X509_STRICT, CVE-2021-3449 NULL pointer deref in signature_algorithms processing af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List, Third Party Advisory
Oracle Critical Patch Update Advisory - July 2021 af854a3a-2127-422b-91ae-364da2661108 www.oracle.com Patch, Third Party Advisory
oss-security - OpenSSL 1.1.1 CVE-2021-3450 CA certificate check bypass with X509_V_FLAG_X509_STRICT, CVE-2021-3449 NULL pointer deref in signature_algorithms processing af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List, Third Party Advisory
McAfee Security Bulletin - Status and updates for OpenSSL vulnerabilities (CVE-2021-3450 and 2021-3449) af854a3a-2127-422b-91ae-364da2661108 kc.mcafee.com Third Party Advisory
OpenSSL: Multiple vulnerabilities (GLSA 202103-03) — Gentoo security af854a3a-2127-422b-91ae-364da2661108 security.gentoo.org Third Party Advisory
oss-security - Re: OpenSSL 1.1.1 CVE-2021-3450 CA certificate check bypass with X509_V_FLAG_X509_STRICT, CVE-2021-3449 NULL pointer deref in signature_algorithms processing af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List, Third Party Advisory
March 2021 OpenSSL Vulnerabilities in NetApp Products | NetApp Product Security af854a3a-2127-422b-91ae-364da2661108 security.netapp.com Third Party Advisory
OpenSSL Security Advisory af854a3a-2127-422b-91ae-364da2661108 mta.openssl.org Mailing List, Vendor Advisory
Oracle Critical Patch Update Advisory - July 2022 af854a3a-2127-422b-91ae-364da2661108 www.oracle.com Patch, Third Party Advisory
Oracle Critical Patch Update Advisory - April 2021 af854a3a-2127-422b-91ae-364da2661108 www.oracle.com Patch, Third Party Advisory
[R1] Nessus Network Monitor 5.13.1 Fixes Multiple Third-party Vulnerabilities - Security Advisory | Tenable® af854a3a-2127-422b-91ae-364da2661108 www.tenable.com Third Party Advisory
security.FreeBSD.org/advisories/FreeBSD-SA-21:07.openssl.asc af854a3a-2127-422b-91ae-364da2661108 security.FreeBSD.org Third Party Advisory
[R1] Nessus 8.13.2 Fixes Multiple Third-party Vulnerabilities - Security Advisory | Tenable® af854a3a-2127-422b-91ae-364da2661108 www.tenable.com Third Party Advisory
www.openssl.org/news/secadv/20210325.txt af854a3a-2127-422b-91ae-364da2661108 www.openssl.org Vendor Advisory
git.openssl.org Git - openssl.git/commitdiff af854a3a-2127-422b-91ae-364da2661108 git.openssl.org
[R1] Nessus Agent 8.2.4 Fixes Multiple Vulnerabilities - Security Advisory | Tenable® af854a3a-2127-422b-91ae-364da2661108 www.tenable.com Third Party Advisory
cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf af854a3a-2127-422b-91ae-364da2661108 cert-portal.siemens.com Third Party Advisory
Public KB - SA44845 - OpenSSL Security Advisory CVE-2021-3450 af854a3a-2127-422b-91ae-364da2661108 kb.pulsesecure.net Third Party Advisory
git.openssl.org Git - openssl.git/commitdiff MITRE git.openssl.org
[SECURITY] Fedora 34 Update: openssl-1.1.1k-1.fc34 - package-announce - Fedora Mailing-Lists MITRE lists.fedoraproject.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

CNA: Benjamin Kaduk (Akamai), Xiang Ding (Akamai), others at Akamai (en)

Legacy QID Mappings

  • 159128 Oracle Enterprise Linux Security Update for openssl (ELSA-2021-1024)
  • 159138 Oracle Enterprise Linux Security Update for openssl (ELSA-2021-9151)
  • 179935 Debian Security Update for Open Secure Sockets Layer (OpenSSL) (CVE-2021-3450)
  • 239185 Red Hat Update for openssl (RHSA-2021:1024)
  • 239247 Red Hat Update for Red Hat JBoss Core Services Apache HTTP Server 2.4.37 SP7 (RHSA-2021:1199)
  • 239730 Red Hat Update for red hat jboss web server 5.4.2 (RHSA-2021:1195)
  • 239739 Red Hat Update for red hat jboss web server 3.1 service pack 12 (RHSA-2021:1202)
  • 281398 Fedora Security Update for Open Secure Sockets Layer (OpenSSL) (FEDORA-2021-cbf14ab8f9)
  • 296053 Oracle Solaris 11.4 Support Repository Update (SRU) 35.94.4 Missing (CPUJUL2021)
  • 296059 Oracle Solaris 11.4 Support Repository Update (SRU) 36.0.1.101.2 Missing (CPUJUL2021)
  • 316994 Cisco Internetwork Operating System (IOS-XE) Vulnerability in Open Secure Sockets Layer (OpenSSL) Affecting Cisco Products (cisco-sa-openssl-2021-GHY28dJd)
  • 316995 Cisco Nexus Operating System (NX-OS) Vulnerability in Open Secure Sockets Layer (OpenSSL) Affecting Cisco Products (cisco-sa-openssl-2021-GHY28dJd)
  • 316996 Cisco Web Security Appliance Vulnerability in Open Secure Sockets Layer (OpenSSL) Affecting Cisco Products (cisco-sa-openssl-2021-GHY28dJd)
  • 352258 Amazon Linux Security Advisory for openssl11: ALAS2-2021-1622
  • 357333 Amazon Linux Security Advisory for edk2 : ALAS2-2024-2502
  • 375520 Mysql Workbench Critical Patch Update April 2021
  • 375559 Python Open Secure Sockets Layer (OpenSSL) Library Vulnerability
  • 375656 Tenable Nessus Agent Multiple Vulnerabilities (TNS-2021-08)
  • 375720 Oracle PeopleSoft Enterprise PeopleTools Product Multiple Vulnerabilities (CPUJUL2021)
  • 377109 Alibaba Cloud Linux Security Update for Open Secure Sockets Layer (OpenSSL) (ALINUX3-SA-2021:0021)
  • 38837 OpenSSL Security Update (OpenSSL Security Advisory 20210325)
  • 500498 Alpine Linux Security Update for Open Secure Sockets Layer (OpenSSL)
  • 500566 Alpine Linux Security Update for Open Secure Sockets Layer (OpenSSL)
  • 500765 Alpine Linux Security Update for openssl
  • 501165 Alpine Linux Security Update for openssl
  • 501984 Alpine Linux Security Update for Open Secure Sockets Layer3 (OpenSSL3)
  • 502903 Alpine Linux Security Update for openssl1.1-compat
  • 504257 Alpine Linux Security Update for openssl
  • 591311 Bosch Rexroth PRA-ES8P2S Ethernet-Switch Multiple Vulnerabilities (BOSCH-SA-247053-BT)
  • 690068 Free Berkeley Software Distribution (FreeBSD) Security Update for mysql (38a4a043-e937-11eb-9b84-d4c9ef517024)
  • 690183 Free Berkeley Software Distribution (FreeBSD) Security Update for node.js (c0c1834c-9761-11eb-acfd-0022489ad614)
  • 690185 Free Berkeley Software Distribution (FreeBSD) Security Update for Open Secure Sockets Layer (OpenSSL) (5a668ab3-8d86-11eb-b8d6-d4c9ef517024)
  • 710009 Gentoo Linux OpenSSL Multiple Vulnerabilities (GLSA 202103-03)
  • 730135 Cisco Prime Infrastructure Denial of Service (DoS) Vulnerability in Open Secure Sockets Layer (OpenSSL) Affecting Cisco Products (cisco-sa-openssl-2021-GHY28dJd)
  • 730228 McAfee Web Gateway Multiple Vulnerabilities (WP-3445, WP-3483, WP-3527, WP-3528, WP-3547, WP-3584,WP-3589,WP-3611)
  • 750833 OpenSUSE Security Update for nodejs12 (openSUSE-SU-2021:2327-1)
  • 750837 SUSE Enterprise Linux Security Update for nodejs10 (SUSE-SU-2021:2353-1)
  • 750840 OpenSUSE Security Update for nodejs10 (openSUSE-SU-2021:2353-1)
  • 750858 OpenSUSE Security Update for nodejs10 (openSUSE-SU-2021:1061-1)
  • 750859 OpenSUSE Security Update for nodejs12 (openSUSE-SU-2021:1059-1)
  • 91783 IBM Integration Bus and IBM App Connect Enterprise Open Secure Sockets Layer (OpenSSL) Multiple Vulnerabilities (6466315)
  • 91784 IBM Integration Bus and IBM App Connect Enterprise Node.js Multiple Vulnerabilities (6467639)
  • 91822 Microsoft Visual Studio Security Update for October 2021
  • 940369 AlmaLinux Security Update for Open Secure Sockets Layer (OpenSSL) (ALSA-2021:1024)
  • 960860 Rocky Linux Security Update for Open Secure Sockets Layer (OpenSSL) (RLSA-2021:1024)

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