CVE-2020-15646
Status: ModifiedMedium (5.9)—
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.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
- Base score: 5.9
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.96%
- Percentile among all scored CVEs: 60
- Score date: 10/8/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
CWEs
- NVD-CWE-noinfo
References
Raw JSON (NVD)
Show
{
"id": "CVE-2020-15646",
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"affected": [
{
"source": "security@mozilla.org",
"affectedData": [
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"vendor": "Mozilla",
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"published": "2020-10-08T14:15:12.483",
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"tags": [
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"vulnStatus": "Modified",
"weaknesses": [
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"descriptions": [
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"lang": "en",
"value": "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."
},
{
"lang": "es",
"value": "Si un atacante intercepta el intento inicial de Thunderbird de llevar a cabo los ajustes automáticos de la cuenta mediante el mecanismo de detección automática de Microsoft Exchange, y el atacante envía una respuesta diseñada, entonces Thunderbird envía el nombre de usuario y contraseña por medio de https hacia un servidor controlado por el atacante. Esta vulnerabilidad afecta a Thunderbird versiones anteriores a 68.10.0"
}
],
"lastModified": "2026-06-17T02:56:58.510",
"configurations": [
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"sourceIdentifier": "security@mozilla.org"
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