CVE-2020-15646

CVE-2020-15646 is a medium-severity vulnerability in Mozilla Thunderbird with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

If an attacker intercepts Thunderbird's initial attempt to perform automatic account setup using the Microsoft Exchange autodiscovery mechanism, and the attacker sends a crafted response, then Thunderbird sends username and password over https to a server controlled by the attacker. This vulnerability affects Thunderbird < 68.10.0.

Frequently asked questions

What is CVE-2020-15646?
If an attacker intercepts Thunderbird's initial attempt to perform automatic account setup using the Microsoft Exchange autodiscovery mechanism, and the attacker sends a crafted response, then Thunderbird sends username and password over https to a server controlled by the attacker. This vulnerability affects Thunderbird < 68.10.0.
How severe is CVE-2020-15646?
CVE-2020-15646 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2020-15646 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-15646?
CVE-2020-15646 affects Mozilla Thunderbird. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-15646?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-15646 published?
CVE-2020-15646 was published on 2020-10-08 and last updated on 2026-06-17.

References

Affected products (1)

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