CVE-2021-38502

MEDIUM
5.9
CVSS Score
Published: November 3, 2021 at 12:02 AM UTC
Updated: June 17, 2026 at 04:02 AM UTC
2 products affected across 2 vendorsDebian LinuxThunderbird

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Severity
MEDIUM5.9
Exploit prediction
EPSS 1%

Description

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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 91.2
Affected range stops below 91.2, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (4)

x_refsource_MISCIssue TrackingPermissions RequiredVendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1733366
Mailing Listx_refsource_MLISTThird Party Advisory
https://lists.debian.org/debian-lts-announce/2022/01/msg00001.html
Vendor Advisoryx_refsource_DEBIANIssue TrackingThird Party Advisory
https://www.debian.org/security/2022/dsa-5034

CVSS

Attack Vector
NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
NVD-CWE-Other

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