Mozilla: >> Thunderbird >> 135.0 Security Vulnerabilities
Thunderbird processes the X-Mozilla-External-Attachment-URL header to handle attachments which can be hosted externally. When an email is opened, Thunderbird accesses the specified URL to determine file size, and navigates to it when the user clicks the attachment. Because the URL is not validated or sanitized, it can reference internal resources like chrome:// or SMB share file:// links, potentially leading to hashed Windows credential leakage and opening the door to more serious security issues. This vulnerability affects Thunderbird < 137.0.2 and Thunderbird < 128.9.2.
CVSS Score
6.3
EPSS Score
0.0
Published
2025-04-15
When an email contains multiple attachments with external links via the X-Mozilla-External-Attachment-URL header, only the last link is shown when hovering over any attachment. Although the correct link is used on click, the misleading hover text could trick users into downloading content from untrusted sources. This vulnerability affects Thunderbird < 137.0.2 and Thunderbird < 128.9.2.
CVSS Score
6.4
EPSS Score
0.0
Published
2025-04-15
By crafting a malformed file name for an attachment in a multipart message, an attacker can trick Thunderbird into including a directory listing of /tmp when the message is forwarded or edited as a new message. This vulnerability could allow attackers to disclose sensitive information from the victim's system. This vulnerability is not limited to Linux; similar behavior has been observed on Windows as well. This vulnerability affects Thunderbird < 137.0.2 and Thunderbird < 128.9.2.
CVSS Score
6.3
EPSS Score
0.0
Published
2025-04-15
JavaScript code running while transforming a document with the XSLTProcessor could lead to a use-after-free. This vulnerability affects Firefox < 137, Firefox ESR < 115.22, Firefox ESR < 128.9, Thunderbird < 137, and Thunderbird < 128.9.
CVSS Score
6.5
EPSS Score
0.002
Published
2025-04-01
A crafted URL containing specific Unicode characters could have hidden the true origin of the page, resulting in a potential spoofing attack. This vulnerability affects Firefox < 137, Firefox ESR < 128.9, Thunderbird < 137, and Thunderbird < 128.9.
CVSS Score
7.3
EPSS Score
0.001
Published
2025-04-01
Memory safety bugs present in Firefox 136, Thunderbird 136, Firefox ESR 128.8, and Thunderbird 128.8. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 137, Firefox ESR < 128.9, Thunderbird < 137, and Thunderbird < 128.9.
CVSS Score
8.1
EPSS Score
0.001
Published
2025-04-01
An attacker could read 32 bits of values spilled onto the stack in a JIT compiled function. This vulnerability affects Firefox < 137 and Thunderbird < 137.
CVSS Score
6.5
EPSS Score
0.0
Published
2025-04-01
Leaking of file descriptors from the fork server to web content processes could allow for privilege escalation attacks. This vulnerability affects Firefox < 137 and Thunderbird < 137.
CVSS Score
7.4
EPSS Score
0.0
Published
2025-04-01
After selecting a malicious Windows `.url` shortcut from the local filesystem, an unexpected file could be uploaded.
*This bug only affects Firefox on Windows. Other operating systems are unaffected.* This vulnerability affects Firefox < 137 and Thunderbird < 137.
CVSS Score
7.7
EPSS Score
0.0
Published
2025-04-01
Memory safety bugs present in Firefox 136 and Thunderbird 136. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 137 and Thunderbird < 137.
CVSS Score
8.1
EPSS Score
0.0
Published
2025-04-01