CVE-2025-8028: Vulnerability in Mozilla Firefox
On arm64, a WASM `br_table` instruction with a lot of entries could lead to the label being too far from the instruction causing truncation and incorrect computation of the branch address. This vulnerability was fixed in Firefox 141, Firefox ESR 115.26, Firefox ESR 128.13, Firefox ESR 140.1, Thunderbird 141, Thunderbird 128.13, and Thunderbird 140.1.
AI Analysis
Technical Summary
On arm64 architectures, a WebAssembly br_table instruction with a large number of entries could cause the label to be too distant from the instruction, leading to truncation and incorrect computation of the branch address. This flaw could result in incorrect program behavior or potential exploitation. The vulnerability is tracked as CVE-2025-8028 and was fixed in Firefox 141, Firefox ESR 115.26, 128.13, 140.1, Thunderbird 141, 128.13, and 140.1. The issue is part of a set of high-impact memory safety bugs addressed in these releases. The CVSS v3.1 base score is 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating remote exploitability without privileges or user interaction, with high impact on confidentiality, integrity, and availability.
Potential Impact
The vulnerability allows remote attackers to cause incorrect computation of branch addresses in WebAssembly code on arm64 platforms, potentially leading to memory corruption or arbitrary code execution. The CVSS score of 9.8 reflects critical severity with full impact on confidentiality, integrity, and availability. Exploitation could allow attackers to execute arbitrary code or cause denial of service without requiring user interaction or privileges.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 141, Firefox ESR 115.26, 128.13, 140.1, and Thunderbird 141, 128.13, and 140.1. Users and administrators should update affected products to these versions or later to remediate the issue. Patch status is confirmed by Mozilla advisories. No additional mitigations are required beyond applying these updates.
CVE-2025-8028: Vulnerability in Mozilla Firefox
Description
On arm64, a WASM `br_table` instruction with a lot of entries could lead to the label being too far from the instruction causing truncation and incorrect computation of the branch address. This vulnerability was fixed in Firefox 141, Firefox ESR 115.26, Firefox ESR 128.13, Firefox ESR 140.1, Thunderbird 141, Thunderbird 128.13, and Thunderbird 140.1.
CVSS v3.1
Score 9.8critical
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
On arm64 architectures, a WebAssembly br_table instruction with a large number of entries could cause the label to be too distant from the instruction, leading to truncation and incorrect computation of the branch address. This flaw could result in incorrect program behavior or potential exploitation. The vulnerability is tracked as CVE-2025-8028 and was fixed in Firefox 141, Firefox ESR 115.26, 128.13, 140.1, Thunderbird 141, 128.13, and 140.1. The issue is part of a set of high-impact memory safety bugs addressed in these releases. The CVSS v3.1 base score is 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating remote exploitability without privileges or user interaction, with high impact on confidentiality, integrity, and availability.
Potential Impact
The vulnerability allows remote attackers to cause incorrect computation of branch addresses in WebAssembly code on arm64 platforms, potentially leading to memory corruption or arbitrary code execution. The CVSS score of 9.8 reflects critical severity with full impact on confidentiality, integrity, and availability. Exploitation could allow attackers to execute arbitrary code or cause denial of service without requiring user interaction or privileges.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 141, Firefox ESR 115.26, 128.13, 140.1, and Thunderbird 141, 128.13, and 140.1. Users and administrators should update affected products to these versions or later to remediate the issue. Patch status is confirmed by Mozilla advisories. No additional mitigations are required beyond applying these updates.
Technical Details
- Data Version
- 5.1
- Assigner Short Name
- mozilla
- Date Reserved
- 2025-07-22T10:13:49.236Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2025-56/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2025-57/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2025-58/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2025-59/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2025-61/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2025-62/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2025-63/","vendor":"Mozilla"}]
Threat ID: 687ffd50a915ff00f7fb595c
Added to database: 07/22/2025, 21:06:24 UTC
Last enriched: 07/29/2026, 21:22:13 UTC
Last updated: 09/10/2026, 19:36:52 UTC
Views: 119
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