How severe is CVE-2009-0127?

CVE-2009-0127 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2009-0127 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-0127?

CVE-2009-0127 affects Heikkitoivonen M2crypto. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2009-0127?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2009-0127 published?

CVE-2009-0127 was published on 2009-01-15 and last updated on 2026-06-16.

CVE-2009-0127

CVE-2009-0127 is a medium-severity vulnerability in Heikkitoivonen M2crypto with a CVSS 2.0 base score of 5.0. 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: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Heikkitoivonen M2crypto
Published: 2009-01-15
Last modified: 2026-06-16

Description

M2Crypto does not properly check the return value from the OpenSSL EVP_VerifyFinal, DSA_verify, ECDSA_verify, DSA_do_verify, and ECDSA_do_verify functions, which might allow remote attackers to bypass validation of the certificate chain via a malformed SSL/TLS signature, a similar vulnerability to CVE-2008-5077. NOTE: a Linux vendor disputes the relevance of this report to the M2Crypto product because "these functions are not used anywhere in m2crypto.

Frequently asked questions

What is CVE-2009-0127?: M2Crypto does not properly check the return value from the OpenSSL EVP_VerifyFinal, DSA_verify, ECDSA_verify, DSA_do_verify, and ECDSA_do_verify functions, which might allow remote attackers to bypass validation of the certificate chain via a malformed SSL/TLS signature, a similar vulnerability to CVE-2008-5077. NOTE: a Linux vendor disputes the relevance of this report to the M2Crypto product because "these functions are not used anywhere in m2crypto.
How severe is CVE-2009-0127?: CVE-2009-0127 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2009-0127 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-0127?: CVE-2009-0127 affects Heikkitoivonen M2crypto. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2009-0127?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2009-0127 published?: CVE-2009-0127 was published on 2009-01-15 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:heikkitoivonen:m2crypto:-:*:*:*:*:*:*:*

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