CVE-2026-103418
Universal XSS via the HTML language attribute in Translation Services
Firefox for iOS directly interpolated the page’s HTML language attribute into translation JavaScript, allowing attacker-controlled markup to execute code in Firefox’s privileged content world and bypass the page’s Content Security Policy. This vulnerability was fixed in Firefox for iOS 157.1.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
8.8
Universal XSS via the HTML language attribute in Translation Services
Firefox for iOS directly interpolated the page’s HTML language attribute into translation JavaScript, allowing attacker-controlled markup to execute code in Firefox’s privileged content world and bypass the page’s Content Security Policy. This vulnerability was fixed in Firefox for iOS 157.1.
- Record
CVE-2026-103418- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2026-98339
8.8
Firefox for iOS directly interpolated the page’s HTML language attribute into translation JavaScript, allowing attacker-controlled markup to execute code in Firefox’s privileged content world and bypass the page’s Content Security Policy. This vulnerability was fixed in Firefox for iOS 157.1.
- Record
EUVD-2026-98339- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-7fw9-g4rg-xvqv
8.8
Firefox for iOS directly interpolated the page’s HTML language attribute into translation...
Firefox for iOS directly interpolated the page’s HTML language attribute into translation JavaScript, allowing attacker-controlled markup to execute code in Firefox’s privileged content world and bypass the page’s Content Security Policy. This vulnerability was fixed in Firefox for iOS 157.1.
- Record
GHSA-7fw9-g4rg-xvqv- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
8.8
Firefox for iOS directly interpolated the page’s HTML language attribute into translation JavaScript, allowing attacker-controlled markup to execute code in Firefox’s privileged content world and bypass the page’s Content Security Policy. This vulnerability was fixed in Firefox for iOS 157.1.
- Record
CVE-2026-103418- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-103418 is a high vulnerability (CVSS 8.8) in Mozilla Firefox For Ios, published October 13, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.30%, the 23rd percentile. No source names a fixed version.