How severe is CVE-2020-6793?

CVE-2020-6793 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 high, integrity none, and availability none.

Is CVE-2020-6793 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-6793?

CVE-2020-6793 affects Mozilla Thunderbird. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-6793?

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

When was CVE-2020-6793 published?

CVE-2020-6793 was published on 2020-03-02 and last updated on 2026-06-17.

CVE-2020-6793

CVE-2020-6793 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-908.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-908
Affected product: Mozilla Thunderbird
Published: 2020-03-02
Last modified: 2026-06-17

Description

When processing an email message with an ill-formed envelope, Thunderbird could read data from a random memory location. This vulnerability affects Thunderbird < 68.5.

Frequently asked questions

What is CVE-2020-6793?: When processing an email message with an ill-formed envelope, Thunderbird could read data from a random memory location. This vulnerability affects Thunderbird < 68.5.
How severe is CVE-2020-6793?: CVE-2020-6793 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 high, integrity none, and availability none.
Is CVE-2020-6793 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-6793?: CVE-2020-6793 affects Mozilla Thunderbird. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-6793?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-6793 published?: CVE-2020-6793 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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