CVE-2026-74935: Vulnerability in Mozilla Firefox
CVE-2026-74935 is a high-severity privilege escalation vulnerability in the DOM Networking component of Mozilla Firefox. It allows an unprivileged attacker to escalate privileges within the browser environment. This vulnerability was fixed in Firefox 154 and Firefox ESR versions 115.39, 140.14, and 153.1, as well as corresponding Thunderbird versions. The vulnerability has a CVSS score of 8.8, indicating a critical impact on confidentiality, integrity, and availability. No known exploits in the wild have been reported. Users are advised to update to the fixed versions to mitigate the risk.
AI Analysis
Technical Summary
CVE-2026-74935 is a privilege escalation vulnerability affecting the DOM Networking component in Mozilla Firefox. The flaw allows an attacker to gain elevated privileges, potentially compromising browser security. Mozilla fixed this issue in Firefox 154 and Firefox ESR 115.39, 140.14, and 153.1 releases. The vulnerability carries a CVSS 3.1 base score of 8.8 (AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H), indicating it is remotely exploitable with low attack complexity, no privileges required, but user interaction is needed. The impact includes high confidentiality, integrity, and availability consequences. The vendor advisory confirms the fix and no active exploitation has been observed.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to escalate privileges within the Firefox browser, leading to potential full compromise of the browser environment. The CVSS score of 8.8 reflects high impact on confidentiality, integrity, and availability. However, there are no known exploits in the wild at this time.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 154, Firefox ESR 115.39, 140.14, and 153.1. Users and administrators should update to these versions or later to remediate the issue. No additional mitigation steps are required beyond applying the official patches.
CVE-2026-74935: Vulnerability in Mozilla Firefox
Description
CVE-2026-74935 is a high-severity privilege escalation vulnerability in the DOM Networking component of Mozilla Firefox. It allows an unprivileged attacker to escalate privileges within the browser environment. This vulnerability was fixed in Firefox 154 and Firefox ESR versions 115.39, 140.14, and 153.1, as well as corresponding Thunderbird versions. The vulnerability has a CVSS score of 8.8, indicating a critical impact on confidentiality, integrity, and availability. No known exploits in the wild have been reported. Users are advised to update to the fixed versions to mitigate the risk.
CVSS v3.1
Score 8.8high
Affected software
Mozilla
Firefox
Mozilla
Thunderbird
pkg:github/mozilla/firefox-esrRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-74935 is a privilege escalation vulnerability affecting the DOM Networking component in Mozilla Firefox. The flaw allows an attacker to gain elevated privileges, potentially compromising browser security. Mozilla fixed this issue in Firefox 154 and Firefox ESR 115.39, 140.14, and 153.1 releases. The vulnerability carries a CVSS 3.1 base score of 8.8 (AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H), indicating it is remotely exploitable with low attack complexity, no privileges required, but user interaction is needed. The impact includes high confidentiality, integrity, and availability consequences. The vendor advisory confirms the fix and no active exploitation has been observed.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to escalate privileges within the Firefox browser, leading to potential full compromise of the browser environment. The CVSS score of 8.8 reflects high impact on confidentiality, integrity, and availability. However, there are no known exploits in the wild at this time.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 154, Firefox ESR 115.39, 140.14, and 153.1. Users and administrators should update to these versions or later to remediate the issue. No additional mitigation steps are required beyond applying the official patches.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-08-17T11:57:27.168Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-74/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-75/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-76/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-77/","vendor":"Mozilla"}]
Threat ID: 6a845502c6e8be0332367399
Added to database: 08/18/2026, 12:50:10 UTC
Last enriched: 09/11/2026, 22:04:06 UTC
Last updated: 10/03/2026, 02:46:06 UTC
Views: 51
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