CVE-2026-20643

A cross-origin issue in the Navigation API was addressed with improved input validation. This issue is fixed in Background Security Improvements for iOS, iPadOS, and macOS, Safari 26.4, iOS 18.7.7 and iPadOS 18.7.7, iOS 26.4 and iPadOS 26.4, macOS Tahoe 26.4, visionOS 26.4. Processing maliciously crafted web content may bypass Same Origin Policy.

Published: 2026-03-17 Last update: 2026-03-25 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-20643 is rated Low Risk (23.2/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.02%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-20643

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-03-18 — 0.02% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-20643

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.4 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 2.5 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-20643

OS Trackers for CVE-2026-20643

vendor priority summary link
debian end-of-life CVE-2026-20643 end-of-life priority: Debian including 2 source packages (webkit2gtk, wpewebkit), 10 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 5, resolved 5. https://security-tracker.debian.org/tracker/CVE-2026-20643
redhat medium — https://access.redhat.com/security/cve/CVE-2026-20643
suse medium — https://www.suse.com/security/cve/CVE-2026-20643/
ubuntu medium CVE-2026-20643 medium priority: Ubuntu including 5 source packages (qtwebkit-opensource-src, qtwebkit-source, webkit2gtk, webkitgtk, wpewebkit), 31 status rows across 7 suites (bionic, focal, jammy, noble, questing, upstream, xenial): ignored 14, DNE 9, needs-triage 4, needed 3, released 1. https://ubuntu.com/security/CVE-2026-20643

Affected software / configurations for CVE-2026-20643

Vendor Product Version Raw CPE
apple ipados < 26.3.1 cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
apple iphone_os < 26.3.1 cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
apple macos < 26.3.1 cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*

References for CVE-2026-20643

cvelogic Threat Intelligence