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CVE

DEBIAN-CVE-2026-4371

A malicious mail server could send malformed strings with negative lengths, causing the parser to read memory outside the buffer.
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CVE

DEBIAN-CVE-2026-4371

A malicious mail server could send malformed strings with negative lengths, causing the parser to read memory outside the buffer.

A malicious mail server could send malformed strings with negative lengths, causing the parser to read memory outside the buffer. If a mail server or connection to a mail server were compromised, an attacker could cause the parser to malfunction, potentially crashing Thunderbird or leaking sensitive data. This vulnerability was fixed in Thunderbird 149 and Thunderbird 140.9.

Package Versions Affected

Package Version
patch Availability
No items found.

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CVSS Version

Severity
Base Score
CVSS Version
Score Vector
C
H
U
-
C
H
U
0
-
3.1
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H
C
H
U
-

Related Resources

No items found.

References

https://security-tracker.debian.org/tracker/CVE-2026-4371

Severity

7.4

CVSS Score
0
10

Basic Information

Ecosystem
Base CVSS
7.4
EPSS Probability
0%
EPSS Percentile
0%
Introduced Version
0
Fix Available
1:140.9.0esr-1~deb11u1,1:140.9.0esr-1~deb12u1,1:140.9.0esr-1~deb13u1,1:140.9.0esr-1

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