Uninitialized memory disclosure and out-of-bounds read in POP3 and SMTP NTLM authentication (Mozilla Thunderbird)

CVE-2026-113868
MEDIUM 5.3

At a glance

Source
NVD
EPSS
EPSS 0.43 % · percentile 37 ()
State
PUBLISHED
Published
Updated
Assigner
mozilla
NVD status
Awaiting Analysis

Description

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.

Weaknesses (CWE)

  • CWE-125 — Out-of-bounds Read

References

Scores

VersionScoreVectorScored by
CVSS 3.1MEDIUM 5.3CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:HCISA-ADP
CVSS 3.1MEDIUM 5.3CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:HNVD · 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary)

European references

CERT-FR advisories

Affected products

ProductVersions
Mozilla · Thunderbirdunaffected 153.5.1 ≤ 153.* ; unaffected 158.0.1 ≤ *

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD