CVE-2021-3450

HIGHNVD 7.47.4—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.4 under NVD CVSS v3. EPSS exploit probability: 0.5%, top 34% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
Elevated
7.4
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 18%CVSS: 7.4Exploit: NoneExposed: 0

A fix is available — apply it.

The 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).

CVSS v3
7.4
EG Score
7.4(medium)
EPSS
96.9%
KEV
Not listed

Published

March 25, 2021

Last Modified

November 21, 2024

References (48)

Patch Availability(7)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatjbcs-httpd24-openssl-pkcs11-0:0.4.10-20.jbcs.el72021-04-14redhat
redhatopenssl2021-04-14redhat
redhattomcat-native-0:1.2.23-24.redhat_24.ep7.el72021-04-14redhat
redhatpatch2021-04-14redhat
redhatjws5-tomcat-native-0:1.2.25-4.redhat_4.el8jws2021-04-14redhat
redhatredhat-virtualization-host-0:4.4.5-20210330.0.el8_32021-04-14redhat
redhatopenssl-1:1.1.1g-15.el8_32021-03-30redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)
crates.io(1)
PackageVulnerable rangeFixed inDependents
openssl-src—111.15.0—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(9)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 7× in last 7d / 42× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-11 08:25 UTCEPSS rescore
  2. 2026-07-11 08:25 UTCEPSS rescore
  3. 2026-07-09 19:07 UTCEPSS rescore
  4. 2026-07-08 15:12 UTCEPSS rescore
  5. 2026-07-07 13:43 UTCEPSS rescore
  6. 2026-07-06 16:25 UTCEPSS rescore
  7. 2026-07-06 16:25 UTCEPSS rescore
  8. 2026-07-02 16:57 UTCEPSS rescore
  9. 2026-07-01 15:04 UTCEPSS rescore
  10. 2026-07-01 06:48 UTCOSV refresh
  11. 2026-06-30 23:20 UTCEPSS rescore
  12. 2026-06-30 23:20 UTCEPSS rescore
  13. 2026-06-28 14:05 UTCEPSS rescore
  14. 2026-06-28 04:54 UTCEPSS rescore
  15. 2026-06-28 04:54 UTCEPSS rescore
  16. 2026-06-27 03:06 UTCEPSS rescore
  17. 2026-06-27 03:06 UTCEPSS rescore
  18. 2026-06-25 13:48 UTCEPSS rescore
  19. 2026-06-25 13:48 UTCEPSS rescore
  20. 2026-06-24 14:03 UTCEPSS rescore
  21. 2026-06-24 14:03 UTCEPSS rescore
  22. 2026-06-23 21:31 UTCEPSS rescore
  23. 2026-06-23 21:31 UTCEPSS rescore
  24. 2026-06-22 14:24 UTCEPSS rescore
  25. 2026-06-21 01:58 UTCEPSS rescore
Show 54 more
  1. 2026-06-21 01:58 UTCEPSS rescore
  2. 2026-06-19 19:24 UTCEPSS rescore
  3. 2026-06-19 19:24 UTCEPSS rescore
  4. 2026-06-18 17:51 UTCEPSS rescore
  5. 2026-06-18 17:51 UTCEPSS rescore
  6. 2026-06-17 17:51 UTCEPSS rescore
  7. 2026-06-17 17:51 UTCEPSS rescore
  8. 2026-06-17 17:51 UTCEPSS rescore
  9. 2026-06-16 17:51 UTCEPSS rescore
  10. 2026-06-16 17:51 UTCEPSS rescore
  11. 2026-06-15 17:46 UTCEPSS rescore
  12. 2026-06-14 23:15 UTCEPSS rescore
  13. 2026-06-14 23:15 UTCEPSS rescore
  14. 2026-06-13 22:58 UTCEPSS rescore
  15. 2026-06-13 22:58 UTCEPSS rescore
  16. 2026-06-13 10:43 UTCOSV refresh
  17. 2026-06-12 23:10 UTCEPSS rescore
  18. 2026-06-11 13:58 UTCEPSS rescore
  19. 2026-06-11 13:58 UTCEPSS rescore
  20. 2026-06-10 22:16 UTCEPSS rescore
  21. 2026-06-10 22:16 UTCEPSS rescore
  22. 2026-06-10 13:20 UTCEPSS rescore
  23. 2026-06-08 14:15 UTCEPSS rescore
  24. 2026-06-08 14:15 UTCEPSS rescore
  25. 2026-06-07 15:23 UTCEPSS rescore
  26. 2026-06-07 15:23 UTCEPSS rescore
  27. 2026-06-06 13:46 UTCEPSS rescore
  28. 2026-06-06 13:46 UTCEPSS rescore
  29. 2026-06-05 22:45 UTCEPSS rescore
  30. 2026-06-05 06:09 UTCEPSS rescore
  31. 2026-06-05 06:09 UTCEPSS rescore
  32. 2026-06-04 13:10 UTCEPSS rescore
  33. 2026-06-04 13:10 UTCEPSS rescore
  34. 2026-06-02 20:11 UTCEPSS rescore
  35. 2026-06-02 20:11 UTCEPSS rescore
  36. 2026-06-01 13:50 UTCEPSS rescore
  37. 2026-06-01 13:50 UTCEPSS rescore
  38. 2026-05-31 22:29 UTCEPSS rescore
  39. 2026-05-31 22:29 UTCEPSS rescore
  40. 2026-05-31 00:15 UTCEPSS rescore
  41. 2026-05-31 00:15 UTCEPSS rescore
  42. 2026-05-29 13:42 UTCEPSS rescore
  43. 2026-05-28 13:43 UTCEPSS rescore
  44. 2026-05-28 13:43 UTCEPSS rescore
  45. 2026-05-27 13:39 UTCEPSS rescore
  46. 2026-05-27 13:39 UTCEPSS rescore
  47. 2026-05-26 19:12 UTCEG score recompute
  48. 2026-05-26 19:12 UTCVendor advisory
  49. 2026-05-26 13:42 UTCEPSS rescore
  50. 2026-05-26 13:42 UTCEPSS rescore
  51. 2026-05-26 07:17 UTCEPSS rescore
  52. 2026-05-26 07:17 UTCEPSS rescore
  53. 2026-05-26 07:17 UTCEPSS rescore
  54. 2026-05-25 10:46 UTCOSV refresh

Frequently asked(5)

What is CVE-2021-3450?
CVE-2021-3450 is a high vulnerability published on March 25, 2021. The X509VFLAGX509STRICT 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…
When was CVE-2021-3450 disclosed?
CVE-2021-3450 was first published in the National Vulnerability Database on March 25, 2021, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-3450 actively exploited?
CVE-2021-3450 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 96.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2021-3450?
CVE-2021-3450 has a CVSS v3 base score of 7.4 (NVD).
How do I remediate CVE-2021-3450?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-3450, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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