CVE-2026-126136
Last modified
CVE-2026-126136 is a vulnerability of currently unknown severity. For Exchange accounts using EWS or Microsoft Graph with OAuth2 authentication, Thunderbird sent the OAuth2 access token to the server even when the configured server URL used unencrypted HTTP. An attacker able to observe network traffic could obtain the token and use it to access the user's mailbox until the token expired.
Description
For Exchange accounts using EWS or Microsoft Graph with OAuth2 authentication, Thunderbird sent the OAuth2 access token to the server even when the configured server URL used unencrypted HTTP. An attacker able to observe network traffic could obtain the token and use it to access the user's mailbox until the token expired. An attacker positioned on the network during account setup could cause such a URL to be configured. This vulnerability was fixed in Thunderbird 160 and Thunderbird 153.7.
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Thunderbird | All versions |
References
Timeline
- Published
- Last Modified
- Status
- Awaiting Analysis
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