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Status published
Medium
CVE-2021-23953
If a user clicked into a specifically crafted PDF, the...
Vulnerability Description
If a user clicked into a specifically crafted PDF, the PDF reader could be confused into leaking cross-origin information, when said information is served as chunked data. This vulnerability affects Firefox < 85, Thunderbird < 78.7, and Firefox ESR < 78.7.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
No credits recorded in the NVD database.
References
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CVE-2025-9184
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CVE-2025-9183
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0
Affected Vendor
Mozilla
View all reports →Affected Software
Firefox, Thunderbird, Firefox ESR
Vulnerable Versions:
< 85, < 78.7
Timeline
Official Publish:
February 26th, 2021
Last Modified:
August 3rd, 2024
Added to House:
July 21st, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
Weaknesses (CWE)
No CWE data available
MITRE ATT&CK TTPs
No associated TTPs found for this vulnerability.