CVE-2025-1015: Vulnerability in Mozilla Thunderbird
The Thunderbird Address Book URI fields contained unsanitized links. This could be used by an attacker to create and export an address book containing a malicious payload in a field. For example, in the “Other” field of the Instant Messaging section. If another user imported the address book, clicking on the link could result in opening a web page inside Thunderbird, and that page could execute (unprivileged) JavaScript. This vulnerability was fixed in Thunderbird 128.7 and Thunderbird 135.
AI Analysis
Technical Summary
The vulnerability involves unsanitized links in Thunderbird's Address Book URI fields, enabling an attacker to create an address book containing malicious payloads. When imported and interacted with by another user, the malicious link could open a web page inside Thunderbird that executes unprivileged JavaScript code. This issue was addressed and fixed in Thunderbird versions 128.7 and 135. The vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation, i.e., Cross-Site Scripting).
Potential Impact
The impact is limited to the execution of unprivileged JavaScript within Thunderbird when a user imports a maliciously crafted address book and clicks on the embedded link. This could potentially lead to limited code execution within the context of Thunderbird but does not escalate privileges or cause direct system compromise. The CVSS vector indicates network attack vector, low attack complexity, no privileges required, user interaction required, and low confidentiality and integrity impact with no availability impact.
Mitigation Recommendations
This vulnerability has been fixed in Thunderbird versions 128.7 and 135. Users and administrators should update to at least Thunderbird 128.7 or later to remediate this issue. Since official fixes are available, applying these updates is the recommended mitigation. No additional action is required once the update is applied.
CVE-2025-1015: Vulnerability in Mozilla Thunderbird
Description
The Thunderbird Address Book URI fields contained unsanitized links. This could be used by an attacker to create and export an address book containing a malicious payload in a field. For example, in the “Other” field of the Instant Messaging section. If another user imported the address book, clicking on the link could result in opening a web page inside Thunderbird, and that page could execute (unprivileged) JavaScript. This vulnerability was fixed in Thunderbird 128.7 and Thunderbird 135.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability involves unsanitized links in Thunderbird's Address Book URI fields, enabling an attacker to create an address book containing malicious payloads. When imported and interacted with by another user, the malicious link could open a web page inside Thunderbird that executes unprivileged JavaScript code. This issue was addressed and fixed in Thunderbird versions 128.7 and 135. The vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation, i.e., Cross-Site Scripting).
Potential Impact
The impact is limited to the execution of unprivileged JavaScript within Thunderbird when a user imports a maliciously crafted address book and clicks on the embedded link. This could potentially lead to limited code execution within the context of Thunderbird but does not escalate privileges or cause direct system compromise. The CVSS vector indicates network attack vector, low attack complexity, no privileges required, user interaction required, and low confidentiality and integrity impact with no availability impact.
Mitigation Recommendations
This vulnerability has been fixed in Thunderbird versions 128.7 and 135. Users and administrators should update to at least Thunderbird 128.7 or later to remediate this issue. Since official fixes are available, applying these updates is the recommended mitigation. No additional action is required once the update is applied.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2025-02-04T07:26:39.563Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2025-10/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2025-11/","vendor":"Mozilla"}]
Threat ID: 69dd057382d89c981f016f94
Added to database: 4/13/2026, 3:02:11 PM
Last enriched: 4/13/2026, 3:19:21 PM
Last updated: 4/14/2026, 6:08:53 AM
Views: 5
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