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Vulnerability details: VCID-65fz-myrg-quey
Vulnerability ID VCID-65fz-myrg-quey
Aliases CVE-2021-23839
Summary openssl: incorrect SSLv2 rollback protection
Status Published
Exploitability 0.5
Weighted Severity 3.3
Risk 1.6
Affected and Fixed Packages Package Details
Weaknesses (3)
CWE-1035 OWASP Top Ten 2017 Category A9 - Using Components with Known Vulnerabilities
CWE-327 Use of a Broken or Risky Cryptographic Algorithm
CWE-937 OWASP Top Ten 2013 Category A9 - Using Components with Known Vulnerabilities
System Score Found at
cvssv3 3.7 https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-23839.json
epss 0.00292 https://api.first.org/data/v1/epss?cve=CVE-2021-23839
epss 0.00292 https://api.first.org/data/v1/epss?cve=CVE-2021-23839
epss 0.00292 https://api.first.org/data/v1/epss?cve=CVE-2021-23839
epss 0.00292 https://api.first.org/data/v1/epss?cve=CVE-2021-23839
epss 0.00292 https://api.first.org/data/v1/epss?cve=CVE-2021-23839
epss 0.00292 https://api.first.org/data/v1/epss?cve=CVE-2021-23839
epss 0.00292 https://api.first.org/data/v1/epss?cve=CVE-2021-23839
epss 0.00292 https://api.first.org/data/v1/epss?cve=CVE-2021-23839
epss 0.00292 https://api.first.org/data/v1/epss?cve=CVE-2021-23839
ssvc Track https://cert-portal.siemens.com/productcert/pdf/ssa-637483.pdf
ssvc Track https://git.openssl.org/gitweb/?p=openssl.git%3Ba=commitdiff%3Bh=30919ab80a478f2d81f2e9acdcca3fa4740cd547
ssvc Track https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44846
ssvc Track https://security.netapp.com/advisory/ntap-20210219-0009/
ssvc Track https://security.netapp.com/advisory/ntap-20240621-0006/
ssvc Track https://www.openssl.org/news/secadv/20210216.txt
ssvc Track https://www.oracle.com/security-alerts/cpuApr2021.html
ssvc Track https://www.oracle.com/security-alerts/cpuapr2022.html
ssvc Track https://www.oracle.com//security-alerts/cpujul2021.html
ssvc Track https://www.oracle.com/security-alerts/cpuoct2021.html
Reference id Reference type URL
https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-23839.json
https://api.first.org/data/v1/epss?cve=CVE-2021-23839
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-23839
https://www.openssl.org/news/secadv/20210216.txt
1930294 https://bugzilla.redhat.com/show_bug.cgi?id=1930294
CVE-2021-23839 https://nvd.nist.gov/vuln/detail/CVE-2021-23839
?p=openssl.git%3Ba=commitdiff%3Bh=30919ab80a478f2d81f2e9acdcca3fa4740cd547 https://git.openssl.org/gitweb/?p=openssl.git%3Ba=commitdiff%3Bh=30919ab80a478f2d81f2e9acdcca3fa4740cd547
No exploits are available.
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N Found at https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-23839.json
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2024-08-01T19:19:45Z/ Found at https://cert-portal.siemens.com/productcert/pdf/ssa-637483.pdf
Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2024-08-01T19:19:45Z/ Found at https://git.openssl.org/gitweb/?p=openssl.git%3Ba=commitdiff%3Bh=30919ab80a478f2d81f2e9acdcca3fa4740cd547
Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2024-08-01T19:19:45Z/ Found at https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44846
Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2024-08-01T19:19:45Z/ Found at https://security.netapp.com/advisory/ntap-20210219-0009/
Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2024-08-01T19:19:45Z/ Found at https://security.netapp.com/advisory/ntap-20240621-0006/
Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2024-08-01T19:19:45Z/ Found at https://www.openssl.org/news/secadv/20210216.txt
Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2024-08-01T19:19:45Z/ Found at https://www.oracle.com/security-alerts/cpuApr2021.html
Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2024-08-01T19:19:45Z/ Found at https://www.oracle.com/security-alerts/cpuapr2022.html
Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2024-08-01T19:19:45Z/ Found at https://www.oracle.com//security-alerts/cpujul2021.html
Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2024-08-01T19:19:45Z/ Found at https://www.oracle.com/security-alerts/cpuoct2021.html
Exploit Prediction Scoring System (EPSS)
Percentile 0.52478
EPSS Score 0.00292
Published At April 1, 2026, 12:55 p.m.
Date Actor Action Source VulnerableCode Version
2026-04-01T14:03:10.510276+00:00 RedHat Importer Import https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-23839.json 38.0.0