How severe is CVE-2023-0430?

CVE-2023-0430 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2023-0430 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-0430?

CVE-2023-0430 affects Mozilla Thunderbird. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-0430?

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

When was CVE-2023-0430 published?

CVE-2023-0430 was published on 2023-06-02 and last updated on 2026-06-17.

CVE-2023-0430

CVE-2023-0430 is a medium-severity vulnerability in Mozilla Thunderbird with a CVSS 3.x base score of 6.5. 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-295.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (29th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Mozilla Thunderbird
Published: 2023-06-02
Last modified: 2026-06-17

Description

Certificate OCSP revocation status was not checked when verifying S/Mime signatures. Mail signed with a revoked certificate would be displayed as having a valid signature. Thunderbird versions from 68 to 102.7.0 were affected by this bug. This vulnerability affects Thunderbird < 102.7.1.

Frequently asked questions

What is CVE-2023-0430?: Certificate OCSP revocation status was not checked when verifying S/Mime signatures. Mail signed with a revoked certificate would be displayed as having a valid signature. Thunderbird versions from 68 to 102.7.0 were affected by this bug. This vulnerability affects Thunderbird < 102.7.1.
How severe is CVE-2023-0430?: CVE-2023-0430 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2023-0430 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-0430?: CVE-2023-0430 affects Mozilla Thunderbird. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-0430?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-0430 published?: CVE-2023-0430 was published on 2023-06-02 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*

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