CVE-2026-20665

This issue was addressed through improved state management. This issue is fixed in Safari 26.4, iOS 18.7.7 and iPadOS 18.7.7, iOS 26.4 and iPadOS 26.4, macOS Tahoe 26.4, tvOS 26.4, visionOS 26.4, watchOS 26.4. Processing maliciously crafted web content may prevent Content Security Policy from being enforced.

Published: 2026-03-25 Last update: 2026-03-25 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-20665 is rated Moderate Risk (42/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.61%). Mandatory action: Review affected assets and schedule remediation.

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-2026-20665

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 2026-06-15 0.16% 0.61% +0.45%
2 2026-03-31 0.12% 0.16% +0.04%
3 2026-03-26 0.12%

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-20665

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L 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:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
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:N)
Data isn’t meaningfully altered or forged.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
3.9 2.5 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-20665

OS Trackers for CVE-2026-20665

vendor priority summary link
debian end-of-life CVE-2026-20665 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-2026-20665
redhat medium https://access.redhat.com/security/cve/CVE-2026-20665
suse medium https://www.suse.com/security/cve/CVE-2026-20665/
ubuntu medium CVE-2026-20665 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-2026-20665

Affected software / configurations for CVE-2026-20665

Vendor Product Version Raw CPE
apple safari < 26.4 cpe:2.3:a:apple:safari:*:*:*:*:*:*:*:*
apple ipados < 18.7.7 cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
apple ipados >= 26.0, < 26.4 cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
apple iphone_os < 18.7.7 cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
apple iphone_os >= 26.0, < 26.4 cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
apple macos < 26.4 cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*
apple tvos < 26.4 cpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*
apple visionos < 26.4 cpe:2.3:o:apple:visionos:*:*:*:*:*:*:*:*
apple watchos < 26.4 cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*

References for CVE-2026-20665

URL Tags
https://support.apple.com/en-us/126792 Release Notes Vendor Advisory
https://support.apple.com/en-us/126793 Release Notes Vendor Advisory
https://support.apple.com/en-us/126794 Release Notes Vendor Advisory
https://support.apple.com/en-us/126797 Release Notes Vendor Advisory
https://support.apple.com/en-us/126798 Release Notes Vendor Advisory
https://support.apple.com/en-us/126799 Release Notes Vendor Advisory
https://support.apple.com/en-us/126800 Release Notes Vendor Advisory
cvelogic Threat Intelligence