Vulnerability · CVE-2026-109772
Same-origin policy bypass in the DevTools component.
Published Oct 13, 2026 · catalog updated Oct 26, 2026 · Same-origin policy bypass in
Last checked Oct 27, 2026. A connected source was read within the last 7 days.
Check if you run it
No confirmed exploitation is on record for CVE-2026-109772. EPSS is 0.18%. Act only if a listed version of Same-origin policy bypass in is installed.
Gaps on this record
- The stored product name is a package slug. The name on this page is taken from the title (Same-origin policy bypass in).
- No version range is stored. A customer cannot check an installed version against this record.
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- Critical9.1
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.18%
- Remediation
- Advisory link
- Affected products
- vendor mozilla
Same-origin policy bypass in the DevTools component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- vendor mozillaversion unspecified
How to fix CVE-2026-109772
No stored fix
No vendor fix text is stored. Use the linked advisory before you change production.
Version check
No version range is stored, so an installed version cannot be checked on this page.
Advisory
Open the bsi record and follow its fix.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-109772. EPSS is 0.18%. Act only if a listed version of Same-origin policy bypass in is installed.
Which versions are affected?
Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS 0.18%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Oct 26, 2026 · BSI CERT-Bund
Detected
CVE-2026-109772 is listed by Mozilla Firefox und Thunderbrid: Mehrere Schwachstellen.
Oct 26, 2026 · EUVD
Updated
Same-origin policy bypass in the DevTools component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.
Sources
- BSI CERT-BundGovernment advisoryCVE-2026-109772
Mozilla Firefox und Thunderbrid: Mehrere Schwachstellen
wid.cert-bund.de - CVE.orgVulnerability recordCVE-2026-109772
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-109772
30-day exploitation probability 0.18%
first.org - EUVDVulnerability recordEUVD-2026-98532
Same-origin policy bypass in the DevTools component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.
euvd.enisa.europa.eu
References
Freshness
Last verified in this catalog Oct 27, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.
- FIRST EPSSOct 27, 2026
- EUVDOct 26, 2026
- CVE.orgOct 26, 2026
- BSI CERT-BundOct 26, 2026