How severe is CVE-2026-9986?

CVE-2026-9986 has a CVSS 3.x base score of 4.2, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity none, and availability low.

Is CVE-2026-9986 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (4th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-9986?

CVE-2026-9986 affects Google Chrome. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-9986?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-9986 have an EU (EUVD) identifier?

Yes. CVE-2026-9986 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-33128.

When was CVE-2026-9986 published?

CVE-2026-9986 was published on 2026-05-28 and last updated on 2026-06-17.

CVE-2026-9986

CVE-2026-9986 is a medium-severity vulnerability in Google Chrome with a CVSS 3.x base score of 4.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 4.2)
EPSS exploit prediction: 0% (4th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-33128
Weakness: CWE-20
Affected product: Google Chrome
Published: 2026-05-28
Last modified: 2026-06-17

Description

Insufficient validation of untrusted input in OptimizationGuide in Google Chrome prior to 148.0.7778.216 allowed a remote attacker who had compromised the renderer process to perform UI spoofing via a crafted HTML page. (Chromium security severity: High)

Frequently asked questions

What is CVE-2026-9986?: Insufficient validation of untrusted input in OptimizationGuide in Google Chrome prior to 148.0.7778.216 allowed a remote attacker who had compromised the renderer process to perform UI spoofing via a crafted HTML page. (Chromium security severity: High)
How severe is CVE-2026-9986?: CVE-2026-9986 has a CVSS 3.x base score of 4.2, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity none, and availability low.
Is CVE-2026-9986 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (4th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-9986?: CVE-2026-9986 affects Google Chrome. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-9986?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-9986 have an EU (EUVD) identifier?: Yes. CVE-2026-9986 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-33128.
When was CVE-2026-9986 published?: CVE-2026-9986 was published on 2026-05-28 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:google:chrome:*:*:*:*:*:*:*:*

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