How severe is CVE-2020-6795?

CVE-2020-6795 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 none, and availability high.

Is CVE-2020-6795 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-6795?

CVE-2020-6795 affects Mozilla Thunderbird. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-6795?

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

When was CVE-2020-6795 published?

CVE-2020-6795 was published on 2020-03-02 and last updated on 2026-06-17.

CVE-2020-6795

CVE-2020-6795 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-476.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Mozilla Thunderbird
Published: 2020-03-02
Last modified: 2026-06-17

Description

When processing a message that contains multiple S/MIME signatures, a bug in the MIME processing code caused a null pointer dereference, leading to an unexploitable crash. This vulnerability affects Thunderbird < 68.5.

Frequently asked questions

What is CVE-2020-6795?: When processing a message that contains multiple S/MIME signatures, a bug in the MIME processing code caused a null pointer dereference, leading to an unexploitable crash. This vulnerability affects Thunderbird < 68.5.
How severe is CVE-2020-6795?: CVE-2020-6795 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 none, and availability high.
Is CVE-2020-6795 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-6795?: CVE-2020-6795 affects Mozilla Thunderbird. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-6795?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-6795 published?: CVE-2020-6795 was published on 2020-03-02 and last updated on 2026-06-17.

References

Affected products (1)

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

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