Chrome is widely deployed; an origin-policy bypass in BackgroundFetch can enable cross-origin data access or actions, making it high-profile and broadly relevant to IT teams.
CVE-2026-121107
Chrome BackgroundFetch origin-policy bypass allowing cross-origin access.
Is CVE-2026-121107 being exploited?
Not confirmed. CVE-2026-121107 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.24% probability of exploitation in the next 30 days.
How severe is CVE-2026-121107?
CVE-2026-121107 is rated High with a CVSS score of 8.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-121107?
Yes. A fix has been recorded for CVE-2026-121107. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-121107 affect?
CVE-2026-121107 affects Google Chrome (desktop) versions prior to 157.0.8103.38, Chromium-based browsers (may be affected). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-121107?
Update Chrome to 157.0.8103.38+ immediately and enforce auto-updates.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Bypass web origin policy via crafted HTML, enabling cross-origin data access or actions from a malicious page (remote attack).
Immediate action required
- affected< 157.0.8103.38
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.
cisa ssvc
- exploitation
- none
- automatable
- no
- technical impact
- total
Assessed by CISA 4 Nov 2026 (SSVC 2.0.3).
timeline
- 3 Nov 2026Published
- 4 Nov 2026CISA SSVC assessment: exploitation none · 1 day later
- 4 Nov 2026CVE record last updated · same day later
- 5 Nov 2026Analysed by vulneraibility.com · 1 day later
- Linkchromereleases.googleblog.com /2026/11/stable-channel-update-for-desktop.html
- Linkissues.chromium.org /issues/485855931
sources
- CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
- NVD: CVSS and CPE data
- CISA Vulnrichment (ADP): SSVC decision points
- FIRST EPSS: exploit probability and percentile
- Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.