CVE-2026-113868 (GCVE-0-2026-113868)

Vulnerability from cvelistv5 – Published: 2026-10-20 19:14 – Updated: 2026-10-20 19:46
VLAI
Title
Uninitialized memory disclosure and out-of-bounds read in POP3 and SMTP NTLM authentication
Summary
When authenticating to a POP3 or SMTP server using NTLM, Thunderbird did not check whether the server's challenge was valid base64. A malicious server could send a challenge that caused Thunderbird to include uninitialized heap memory in its NTLM response, disclosing that memory to the server. A challenge consisting only of base64 padding also caused an out-of-bounds read, crashing Thunderbird. This affected accounts configured to use NTLM or GSSAPI authentication. The uninitialized memory disclosure only affected NTLM. This vulnerability was fixed in Thunderbird 158.0.1 and Thunderbird 153.5.1.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-20 19:41 UTC
CWE
Assigner
mozilla CNA under the mitre root
CNA scorecard E 38/100 over 512 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Mozilla Thunderbird Unaffected: 153.5.1 , ≤ 153.* (rpm)
Unaffected: 158.0.1 , ≤ * (rpm)
guessed Create a notification for this product.
Credits
Nguyen Tuan Hung (VNU HCM - UIT)
Show details on NVD website
To clipboard 

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