CVE-2026-118180
Published:October 27, 2026
Updated:November 04, 2026
When logging in to a Matrix account, Thunderbird used the homeserver address provided in the server's login response without validating it. A malicious or compromised homeserver could provide a file: URL, causing Thunderbird to send all further Matrix requests of that session to local files or, on Windows, to an attacker-controlled network share, which could leak the user's NTLM credentials.
The NTLM credential leak only affects Thunderbird on Windows. Other operating systems are unaffected. This vulnerability was fixed in Thunderbird 159 and Thunderbird 153.6.
Affected Packages
https://github.com/thunderbird/thunderbird-desktop.git (GITHUB):
Affected version(s) >=THUNDERBIRD_154_0b1_RELEASE <THUNDERBIRD_159_0_RELEASE || >=THUNDERBIRD_155_0b1_RELEASE <THUNDERBIRD_159_0_RELEASE || >=THUNDERBIRD_156_0b1_RELEASE <THUNDERBIRD_159_0_RELEASE || >=THUNDERBIRD_157_0b1_RELEASE <THUNDERBIRD_159_0_RELEASE || >=THUNDERBIRD_158_0b1_RELEASE <THUNDERBIRD_159_0_RELEASE || >=THUNDERBIRD_159_0b1_RELEASE <THUNDERBIRD_159_0_RELEASEFix Suggestion:
Update to version THUNDERBIRD_159_0_RELEASEhttps://github.com/thunderbird/thunderbird-desktop.git (GITHUB):
Affected version(s) >=THUNDERBIRD_91_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_92_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_93_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_94_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_95_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_96_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_97_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_98_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_99_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_100_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_101_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_102_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_103_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_104_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_105_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_106_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_107_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_108_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_109_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_110_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_111_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_112_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_113_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_114_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_115_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_116_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_117_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_118_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_119_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_120_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_121_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_122_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_123_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_124_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_125_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_126_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_127_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_128_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_129_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_130_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_131_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_132_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_133_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_134_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_135_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_136_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_137_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_138_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_139_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_140_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_141_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_142_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_143_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_144_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_145_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_146_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_147_0b1_BUILD1 <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_148_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_149_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_150_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_151_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_152_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASE || >=THUNDERBIRD_153_0b1_RELEASE <THUNDERBIRD_153_6_0esr_RELEASEFix Suggestion:
Update to version THUNDERBIRD_153_6_0esr_RELEASERelated Resources (3)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.7
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
NONE
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Weakness Type (CWE)
URL Redirection to Untrusted Site
EPSS
Base Score:
0.17