Read the docs
TI-2021-06205 Aliases CVE-2021-23841GHSA-84rm-qf37-fgc2

Null pointer deref in X509_issuer_and_serial_hash()

Priority LOW 37CWE-476Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 15 fixed, 5 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-476.

Summary

The OpenSSL public API function X509_issuer_and_serial_hash() attempts to create a unique hash value based on the issuer and serial number data contained within an X509 certificate. However it fails to correctly handle any errors that may occur while parsing the issuer field (which might occur if the issuer field is maliciously constructed). This may subsequently result in a NULL pointer deref and a crash leading to a potential denial of service attack. The function X509_issuer_and_serial_hash() is never directly called by OpenSSL itself so applications are only vulnerable if they use this function directly and they use it on certificates that may have been obtained from untrusted sources. OpenSSL versions 1.1.1i and below are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1j. OpenSSL versions 1.0.2x and below are affected by this issue. However OpenSSL 1.0.2 is out of support and no longer receiving public updates. Premium support customers of OpenSSL 1.0.2 should upgrade to 1.0.2y. Other users should upgrade to 1.1.1j. Fixed in OpenSSL 1.1.1j (Affected 1.1.1-1.1.1i). Fixed in OpenSSL 1.0.2y (Affected 1.0.2-1.0.2x).

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0741 94th percentileScored 2026-11-07
Fix Partial openssl-src (crates.io): 111.14.0Red Hat: 8 advisoriesRed Hat: 15 fixed, 5 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
OpenSSLOpenSSLFixed in OpenSSL 1.1.1j (Affected 1.1.1-1.1.1i); Fixed in OpenSSL 1.0.2y (Affected 1.0.2-1.0.2x)—No fix listedCNA
—openssl-src (crates.io)before 111.14.0111.14.0Patch availableGHSA-84rm-qf37-fgc2
  • OpenSSL VendorOpenSSL Affected Fixed in OpenSSL 1.1.1j (Affected 1.1.1-1.1.1i); Fixed in OpenSSL 1.0.2y (Affected 1.0.2-1.0.2x) Fixed in — No fix listed CNA
  • openssl-src (crates.io) Vendor— Affected before 111.14.0 Fixed in 111.14.0 Patch available GHSA-84rm-qf37-fgc2

CPE configurations NVD · 36

CPEVersionsRoleVendor
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*1.0.2 to before 1.0.2y; 1.1.1 to before 1.1.1jVulnerableOpenSSL
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*10.0VulnerableDebian
cpe:2.3:a:tenable:nessus_network_monitor:5.11.0:*:*:*:*:*:*:*5.11.0VulnerableTenable
cpe:2.3:a:tenable:nessus_network_monitor:5.11.1:*:*:*:*:*:*:*5.11.1VulnerableTenable
cpe:2.3:a:tenable:nessus_network_monitor:5.12.0:*:*:*:*:*:*:*5.12.0VulnerableTenable
cpe:2.3:a:tenable:nessus_network_monitor:5.12.1:*:*:*:*:*:*:*5.12.1VulnerableTenable
cpe:2.3:a:tenable:nessus_network_monitor:5.13.0:*:*:*:*:*:*:*5.13.0VulnerableTenable
cpe:2.3:a:tenable:tenable.sc:*:*:*:*:*:*:*:*5.13.0 – 5.17.0VulnerableTenable
cpe:2.3:a:apple:safari:*:*:*:*:*:*:*:*before 14.1.1VulnerableApple
cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*before 14.6VulnerableApple
  • cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* Versions 1.0.2 to before 1.0.2y; 1.1.1 to before 1.1.1j Vulnerable ·OpenSSL
  • cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian
  • cpe:2.3:a:tenable:nessus_network_monitor:5.11.0:*:*:*:*:*:*:* Versions 5.11.0 Vulnerable ·Tenable
  • cpe:2.3:a:tenable:nessus_network_monitor:5.11.1:*:*:*:*:*:*:* Versions 5.11.1 Vulnerable ·Tenable
  • cpe:2.3:a:tenable:nessus_network_monitor:5.12.0:*:*:*:*:*:*:* Versions 5.12.0 Vulnerable ·Tenable
  • cpe:2.3:a:tenable:nessus_network_monitor:5.12.1:*:*:*:*:*:*:* Versions 5.12.1 Vulnerable ·Tenable
  • cpe:2.3:a:tenable:nessus_network_monitor:5.13.0:*:*:*:*:*:*:* Versions 5.13.0 Vulnerable ·Tenable
  • cpe:2.3:a:tenable:tenable.sc:*:*:*:*:*:*:*:* Versions 5.13.0 – 5.17.0 Vulnerable ·Tenable
  • cpe:2.3:a:apple:safari:*:*:*:*:*:*:*:* Versions before 14.1.1 Vulnerable ·Apple
  • cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:* Versions before 14.6 Vulnerable ·Apple
Show 26 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*before 14.6VulnerableApple
cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*11.1 to before 11.4VulnerableApple
cpe:2.3:a:netapp:oncommand_insight:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:a:netapp:oncommand_workflow_automation:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:a:netapp:snapcenter:-:*:*:*:*:*:*:*not specified by NVDVulnerableNetApp
cpe:2.3:a:oracle:business_intelligence:5.5.0.0.0:*:*:*:enterprise:*:*:*5.5.0.0.0VulnerableOracle
cpe:2.3:a:oracle:business_intelligence:5.9.0.0.0:*:*:*:enterprise:*:*:*5.9.0.0.0VulnerableOracle
cpe:2.3:a:oracle:business_intelligence:12.2.1.3.0:*:*:*:enterprise:*:*:*12.2.1.3.0VulnerableOracle
cpe:2.3:a:oracle:business_intelligence:12.2.1.4.0:*:*:*:enterprise:*:*:*12.2.1.4.0VulnerableOracle
cpe:2.3:a:oracle:communications_cloud_native_core_policy:1.15.0:*:*:*:*:*:*:*1.15.0VulnerableOracle
cpe:2.3:a:oracle:enterprise_manager_for_storage_management:13.4.0.0:*:*:*:*:*:*:*13.4.0.0VulnerableOracle
cpe:2.3:a:oracle:enterprise_manager_ops_center:12.4.0.0:*:*:*:*:*:*:*12.4.0.0VulnerableOracle
cpe:2.3:a:oracle:essbase:21.2:*:*:*:*:*:*:*21.2VulnerableOracle
cpe:2.3:a:oracle:graalvm:19.3.5:*:*:*:enterprise:*:*:*19.3.5VulnerableOracle
cpe:2.3:a:oracle:graalvm:20.3.1.2:*:*:*:enterprise:*:*:*20.3.1.2VulnerableOracle
cpe:2.3:a:oracle:graalvm:21.0.0.2:*:*:*:enterprise:*:*:*21.0.0.2VulnerableOracle
cpe:2.3:a:oracle:jd_edwards_world_security:a9.4:*:*:*:*:*:*:*a9.4VulnerableOracle
cpe:2.3:a:oracle:mysql_enterprise_monitor:*:*:*:*:*:*:*:*before 8.0.23VulnerableOracle
cpe:2.3:a:oracle:mysql_server:*:*:*:*:*:*:*:*before 5.7.33; 8.0.15 to before 8.0.23VulnerableOracle
cpe:2.3:a:oracle:peoplesoft_enterprise_peopletools:8.57:*:*:*:*:*:*:*8.57VulnerableOracle
cpe:2.3:a:oracle:peoplesoft_enterprise_peopletools:8.58:*:*:*:*:*:*:*8.58VulnerableOracle
cpe:2.3:a:oracle:peoplesoft_enterprise_peopletools:8.59:*:*:*:*:*:*:*8.59VulnerableOracle
cpe:2.3:a:oracle:zfs_storage_appliance_kit:8.8:*:*:*:*:*:*:*8.8VulnerableOracle
cpe:2.3:a:siemens:sinec_ins:*:*:*:*:*:*:*:*before 1.0VulnerableSiemens
cpe:2.3:a:siemens:sinec_ins:1.0:-:*:*:*:*:*:*1.0VulnerableSiemens
cpe:2.3:a:siemens:sinec_ins:1.0:sp1:*:*:*:*:*:*1.0 sp1VulnerableSiemens
  • cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:* Versions before 14.6 Vulnerable ·Apple
  • cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:* Versions 11.1 to before 11.4 Vulnerable ·Apple
  • cpe:2.3:a:netapp:oncommand_insight:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:a:netapp:oncommand_workflow_automation:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:a:netapp:snapcenter:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·NetApp
  • cpe:2.3:a:oracle:business_intelligence:5.5.0.0.0:*:*:*:enterprise:*:*:* Versions 5.5.0.0.0 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:business_intelligence:5.9.0.0.0:*:*:*:enterprise:*:*:* Versions 5.9.0.0.0 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:business_intelligence:12.2.1.3.0:*:*:*:enterprise:*:*:* Versions 12.2.1.3.0 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:business_intelligence:12.2.1.4.0:*:*:*:enterprise:*:*:* Versions 12.2.1.4.0 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:communications_cloud_native_core_policy:1.15.0:*:*:*:*:*:*:* Versions 1.15.0 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:enterprise_manager_for_storage_management:13.4.0.0:*:*:*:*:*:*:* Versions 13.4.0.0 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:enterprise_manager_ops_center:12.4.0.0:*:*:*:*:*:*:* Versions 12.4.0.0 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:essbase:21.2:*:*:*:*:*:*:* Versions 21.2 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:graalvm:19.3.5:*:*:*:enterprise:*:*:* Versions 19.3.5 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:graalvm:20.3.1.2:*:*:*:enterprise:*:*:* Versions 20.3.1.2 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:graalvm:21.0.0.2:*:*:*:enterprise:*:*:* Versions 21.0.0.2 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:jd_edwards_world_security:a9.4:*:*:*:*:*:*:* Versions a9.4 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:mysql_enterprise_monitor:*:*:*:*:*:*:*:* Versions before 8.0.23 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:mysql_server:*:*:*:*:*:*:*:* Versions before 5.7.33; 8.0.15 to before 8.0.23 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:peoplesoft_enterprise_peopletools:8.57:*:*:*:*:*:*:* Versions 8.57 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:peoplesoft_enterprise_peopletools:8.58:*:*:*:*:*:*:* Versions 8.58 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:peoplesoft_enterprise_peopletools:8.59:*:*:*:*:*:*:* Versions 8.59 Vulnerable ·Oracle
  • cpe:2.3:a:oracle:zfs_storage_appliance_kit:8.8:*:*:*:*:*:*:* Versions 8.8 Vulnerable ·Oracle
  • cpe:2.3:a:siemens:sinec_ins:*:*:*:*:*:*:*:* Versions before 1.0 Vulnerable ·Siemens
  • cpe:2.3:a:siemens:sinec_ins:1.0:-:*:*:*:*:*:* Versions 1.0 Vulnerable ·Siemens
  • cpe:2.3:a:siemens:sinec_ins:1.0:sp1:*:*:*:*:*:* Versions 1.0 sp1 Vulnerable ·Siemens

Remediation

  • Fix · GHSA-84rm-qf37-fgc2 openssl-src (crates.io) Fixed in 111.14.0 Advisory →

Red Hat 8 advisories

  • RHSA-2021:4861 Released 2021-11-30 · Red Hat rating Important
    Red Hat JBoss Web Server 5.6.0 Security release
    • Red Hat JBoss Web Server 5.6 for RHEL 7 Server jws5-tomcat-9.0.50-3.redhat_00004.1.el7jws, jws5-tomcat-admin-webapps-9.0.50-3.redhat_00004.1.el7jws, jws5-tomcat-docs-webapp-9.0.50-3.redhat_00004.1.el7jws +12
    • Red Hat JBoss Web Server 5.6 for RHEL 8 jws5-tomcat-9.0.50-3.redhat_00004.1.el8jws, jws5-tomcat-admin-webapps-9.0.50-3.redhat_00004.1.el8jws, jws5-tomcat-docs-webapp-9.0.50-3.redhat_00004.1.el8jws +10
  • RHSA-2021:4863 Released 2021-11-30 · Red Hat rating Important
    Red Hat JBoss Web Server 5.6.0 Security release
    • Red Hat JBoss Web Server 5
  • RHSA-2021:4614 Released 2021-11-10 · Red Hat rating Moderate
    Red Hat JBoss Core Services Apache HTTP Server 2.4.37 SP10 security update
    • Red Hat JBoss Core Services on RHEL 7 Server jbcs-httpd24-apr-1.6.3-107.jbcs.el7, jbcs-httpd24-apr-devel-1.6.3-107.jbcs.el7, jbcs-httpd24-apr-util-1.6.1-84.jbcs.el7 +36
    • Red Hat JBoss Core Services on RHEL 8 jbcs-httpd24-apr-1.6.3-107.el8jbcs, jbcs-httpd24-apr-devel-1.6.3-107.el8jbcs, jbcs-httpd24-apr-util-1.6.1-84.el8jbcs +36
Show 5 more Red Hat advisories
  • RHSA-2021:4613 Released 2021-11-10 · Red Hat rating Moderate
    Red Hat JBoss Core Services Apache HTTP Server 2.4.37 SP10 security update
    • Red Hat JBoss Core Services
  • RHSA-2021:4198 Released 2021-11-09 · Red Hat rating Moderate
    edk2 security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 8) edk2-20210527gite1999b264f1f-3.el8, edk2-aarch64-20210527gite1999b264f1f-3.el8, edk2-ovmf-20210527gite1999b264f1f-3.el8
  • RHSA-2021:4424 Released 2021-11-09 · Red Hat rating Moderate
    openssl security and bug fix update
    • Red Hat Enterprise Linux BaseOS (v. 8) openssl-1:1.1.1k-4.el8, openssl-devel-1:1.1.1k-4.el8, openssl-libs-1:1.1.1k-4.el8 +1
  • RHSA-2021:3798 Released 2021-10-12 · Red Hat rating Moderate
    openssl security update
    • Red Hat Enterprise Linux Client (v. 7) openssl-1:1.0.2k-22.el7_9, openssl-libs-1:1.0.2k-22.el7_9
    • Red Hat Enterprise Linux Client Optional (v. 7) openssl-devel-1:1.0.2k-22.el7_9, openssl-perl-1:1.0.2k-22.el7_9, openssl-static-1:1.0.2k-22.el7_9
    • Red Hat Enterprise Linux ComputeNode Optional (v. 7) openssl-devel-1:1.0.2k-22.el7_9, openssl-perl-1:1.0.2k-22.el7_9, openssl-static-1:1.0.2k-22.el7_9
    • Red Hat Enterprise Linux Server (v. 7) openssl-1:1.0.2k-22.el7_9, openssl-devel-1:1.0.2k-22.el7_9, openssl-devel-1:1.0.2k-22.el7_9.ppc +2
    • Red Hat Enterprise Linux Server Optional (v. 7) openssl-perl-1:1.0.2k-22.el7_9, openssl-static-1:1.0.2k-22.el7_9, openssl-static-1:1.0.2k-22.el7_9.ppc
    • Red Hat Enterprise Linux Workstation (v. 7) openssl-1:1.0.2k-22.el7_9, openssl-devel-1:1.0.2k-22.el7_9, openssl-libs-1:1.0.2k-22.el7_9
    • Red Hat Enterprise Linux Workstation Optional (v. 7) openssl-perl-1:1.0.2k-22.el7_9, openssl-static-1:1.0.2k-22.el7_9
  • RHSA-2021:1168 Released 2021-04-13 · Red Hat rating Important
    Red Hat Advanced Cluster Management 2.2.2 security and bug fix update
    • Red Hat Advanced Cluster Management for Kubernetes 2.2 for RHEL 7 rhacm2/management-ingress-rhel7, rhacm2/memcached-exporter-rhel7, rhacm2/openshift-hive-rhel7 +2
    • Red Hat Advanced Cluster Management for Kubernetes 2.2 for RHEL 8 rhacm2/acm-must-gather-rhel8, rhacm2/acm-operator-bundle, rhacm2/acmesolver-rhel8 +47

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Advanced Cluster Management for Kubernetes 2AffectedNo fix yet
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix yet
Red Hat Enterprise Linux 8AffectedNo fix planned: Will not fix
Red Hat JBoss Enterprise Application Platform 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2021:4198
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2021:4424
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2021:3798
Red Hat Enterprise Linux Client Optional (v. 7)Fixed RHSA-2021:3798
Red Hat Enterprise Linux ComputeNode Optional (v. 7)Fixed RHSA-2021:3798
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2021:3798
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2021:3798
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2021:3798
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2021:3798
Red Hat JBoss Core ServicesFixed RHSA-2021:4613
Red Hat JBoss Core Services on RHEL 7 ServerFixed RHSA-2021:4614
Red Hat JBoss Core Services on RHEL 8Fixed RHSA-2021:4614
Red Hat JBoss Web Server 5Fixed RHSA-2021:4863
Red Hat JBoss Web Server 5.6 for RHEL 7 ServerFixed RHSA-2021:4861
Red Hat JBoss Web Server 5.6 for RHEL 8Fixed RHSA-2021:4861
Not affected: 1 product
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-23841
  2. 2026-10-03 Alias added: GHSA-84rm-qf37-fgc2

References

Patch 5

Advisory 15

Other 12

  • TI-2022-01915 The c_rehash script allows command injection CVSS 3.1CRITICAL 9.8
  • TI-2021-02645 SM2 Decryption Buffer Overflow CVSS 3.1CRITICAL 9.8
  • TI-2009-03392 The TLS protocol, and the SSL protocol 3.0 and possibly earlier, as used in Microsoft… CVSS 3.1CRITICAL 9.8
  • TI-2022-01176 The c_rehash script allows command injection CVSS 3.1CRITICAL 9.8
  • TI-2014-00154 The (1) TLS and (2) DTLS implementations in OpenSSL 1.0.1 before 1.0.1g do not properly… KEVCVSS 3.1HIGH 7.5
  • TI-2025-14107 Stack buffer overflow in CMS (Auth)EnvelopedData parsing CVSS 3.1HIGH 8.8
See all 312 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences