cbcvebase.
CVE-2021-38502
published 2021-11-03

CVE-2021-38502: Thunderbird ignored the configuration to require STARTTLS security for an SMTP connection. A MITM could perform a downgrade attack to intercept transmitted…

PriorityP432medium5.9CVSS 3.1
AVNACHPRNUINSUCHINAN
EPSS
1.07%
61.3th percentile
Thunderbird ignored the configuration to require STARTTLS security for an SMTP connection. A MITM could perform a downgrade attack to intercept transmitted messages, or could take control of the authenticated session to execute SMTP commands chosen by the MITM. If an unprotected authentication method was configured, the MITM could obtain the authentication credentials, too. This vulnerability affects Thunderbird < 91.2.

Affected

13 ranges
VendorProductVersion rangeFixed in
debiandebian_linux
debiandebian_linux
debiandebian_linux
debianthunderbird< thunderbird 1:91.2.1-1 (bookworm)thunderbird 1:91.2.1-1 (bookworm)
mozillafirefox
mozillathunderbird< 91.291.2
mozillathunderbird>= 0 < 1:91.4.1-1~deb11u11:91.4.1-1~deb11u1
mozillathunderbird>= 0 < 1:91.2.1-11:91.2.1-1
mozillathunderbird>= 0 < 1:91.2.1-11:91.2.1-1
mozillathunderbird>= 0 < 1:91.2.1-11:91.2.1-1
mozillathunderbird>= 0 < 1:91.5.0+build1-0ubuntu0.18.04.11:91.5.0+build1-0ubuntu0.18.04.1
mozillathunderbird>= 0 < 1:91.5.0+build1-0ubuntu0.20.04.11:91.5.0+build1-0ubuntu0.20.04.1
mozillathunderbird>= unspecified < 91.291.2

CVSS provenance

nvdv3.15.9MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
nvdv2.04.3MEDIUMAV:N/AC:M/Au:N/C:P/I:N/A:N
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian5.9MEDIUM
vendor_redhat5.9MEDIUM
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