How severe is CVE-2009-0653?

CVE-2009-0653 has a CVSS 2.0 base score of 7.5, rated high severity.

Is CVE-2009-0653 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-0653?

CVE-2009-0653 affects Openssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2009-0653?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2009-0653 published?

CVE-2009-0653 was published on 2009-02-20 and last updated on 2026-06-16.

CVE-2009-0653

CVE-2009-0653 is a high-severity vulnerability in Openssl with a CVSS 2.0 base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: High (CVSS 2.0 base score 7.5)
EPSS exploit prediction: 1% (63rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Openssl
Published: 2009-02-20
Last modified: 2026-06-16

Description

OpenSSL, probably 0.9.6, does not verify the Basic Constraints for an intermediate CA-signed certificate, which allows remote attackers to spoof the certificates of trusted sites via a man-in-the-middle attack, a related issue to CVE-2002-0970.

Frequently asked questions

What is CVE-2009-0653?: OpenSSL, probably 0.9.6, does not verify the Basic Constraints for an intermediate CA-signed certificate, which allows remote attackers to spoof the certificates of trusted sites via a man-in-the-middle attack, a related issue to CVE-2002-0970.
How severe is CVE-2009-0653?: CVE-2009-0653 has a CVSS 2.0 base score of 7.5, rated high severity.
Is CVE-2009-0653 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (63rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-0653?: CVE-2009-0653 affects Openssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2009-0653?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2009-0653 published?: CVE-2009-0653 was published on 2009-02-20 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:openssl:openssl:0.9.6:*:*:*:*:*:*:*

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Other CWE-287 (Improper Authentication) vulnerabilities

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