5

CVE-2026-9903: google chrome Improper Input Validation

CVSS: 5.0v3.1MediumAnalyzed
AliasesDEBIAN-CVE-2026-9903CGA-7r7r-m9hx-xmwgCGA-rgfg-q3qj-77m7
Published 28-05-2026Last modified 29-05-2026
Open JSON

Vulnerability summary

CVE-2026-9903 is a medium (CVSS 5.0) Improper Input Validation vulnerability in google chrome. EPSS estimates a 0.20% chance of exploitation in the next 30 days, higher than 9.2% of scored vulnerabilities.

Overall risk
20/100
0100
Low · default modelHow is this calculated?
CVSS score
5.0/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.20%
0%100%
Low · +0.04 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 2 · Related 3
OPENSUSE-SU-2026:10906-1OPENSUSE-SU-2026:20849-1CGA-4QJV-G8XF-JH59

Timeline

  1. 28-05-2026
    PublishedVulnerability first disclosed.
  2. 29-05-2026
    Last modifiedVulnerability information updated.

Description

Insufficient validation of untrusted input in Site Isolation in Google Chrome prior to 148.0.7778.216 allowed a remote attacker who had compromised the renderer process to bypass site isolation via a crafted MHTML page. (Chromium security severity: High)

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.20%

Chance of exploitation in the next 30 days

Percentile

9%

Versus all other CVEs

30-day change

+0.04 pp

From 0.16% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.20%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Chainguard1 product
  • chromium< 149.0.7827.53-r0
Debian1 product
  • chromium< 148.0.7778.215-1~deb12u1 | < 148.0.7778.215-1~deb13u1 | < 148.0.7778.215-1
Google1 product
  • chrome≥ 148.0.7778.216, < 148.0.7778.216 | < 148.0.7778.216
Wolfi1 product
  • chromium< 149.0.7827.53-r0

4 vendors · 4 products

References

3 links