What is CVE-2026-9955?

CVE-2026-9955 is a medium-severity vulnerability in Apple Iphone OS, classified under Information Disclosure. CVSS score: 4.3/10. Published 2026-05-28.

How severe is CVE-2026-9955?

Medium severity. CVSS v3 base score is 4.3 out of 10.

Information disclosure in Apple Iphone OS

CVE-2026-9955

Inappropriate implementation in iOS in Google Chrome on iOS prior to 148.0.7778.216 allowed a remote attacker to leak cross-origin data via a crafted HTML page. (Chromium security severity: High)

Vulnerability class: Information Disclosure

Published 2026-05-28 · last modified 2026-07-21.

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.003 (15.9th percentile), scored 2026-10-02.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 16th percentile — 15.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Apple Iphone OS
Google Chrome — versions 148.0.7778.216

Weakness classification (CWE)

CWE-200 — Information Disclosure

References

chromereleases.googleblog.com/2026/05/stable-channel-update-for-desktop_0877304… (Release Notes)
issues.chromium.org/issues/504184408 (Permissions Required, Vendor Advisory)

Frequently asked questions

What is CVE-2026-9955?: CVE-2026-9955 is a medium-severity vulnerability in Apple Iphone OS, classified under Information Disclosure. CVSS score: 4.3/10. Published 2026-05-28.
How severe is CVE-2026-9955?: Medium severity. CVSS v3 base score is 4.3 out of 10.