Security readout for executives and security teams
Plain-English summary
Malicious web content can cause affected Apple platforms to ignore Content Security Policy, a browser safeguard that restricts which content may load. This could expose users or disrupt browsing where security depends on CSP. Apple addressed the flaw through improved state management in the listed fixed releases.
Executive priority
Treat this as a routine but time-sensitive browser and platform update. Prioritize internet-facing user devices and systems accessing sensitive web applications. Escalate where updates cannot be deployed or where critical applications depend heavily on CSP for defense in depth.
Technical view
CVE-2026-20665 is a CWE-693 protection-mechanism failure. Crafted web content may prevent CSP enforcement. The supplied CVSS 3.1 score is 6.5, reflecting network reachability, low complexity, no privileges or interaction, and low confidentiality and availability impact. The sources provide no deeper root-cause details.
Likely exposure
Potential exposure includes Safari and supported Apple devices running iOS, iPadOS, macOS Tahoe, tvOS, visionOS, or watchOS before the named fixed releases. Exact vulnerable version boundaries and affected configurations are not supplied, so organizations should compare inventories against Apple’s advisories.
Exploitation context
The supplied record is not listed in KEV, and the cited sources provide no evidence of active exploitation. This does not prove exploitation is absent. Delivery requires processing maliciously crafted web content, while the CVSS vector records no user interaction.
Researcher notes
The weakness is categorized as CWE-693 and attributed only to state management. Public details do not identify the precise CSP directive, state transition, affected engine component, vulnerable version floor, or bypass scope. Validation should therefore focus on authoritative version status rather than attempting exploit reproduction.
Mitigation direction
- Update Safari to 26.4 or later.
- Update iOS and iPadOS to 18.7.7, 26.4, or later supported releases.
- Update macOS Tahoe, tvOS, visionOS, and watchOS to 26.4 or later.
- Consult the applicable Apple advisory for product-specific deployment guidance.
- Prioritize devices accessing sensitive web applications that rely on CSP.
Validation and detection
- Inventory Safari and Apple operating-system versions across managed devices.
- Confirm installed versions meet or exceed the applicable fixed release.
- Verify update-management reports show successful installation, not merely update availability.
- Review Apple advisories for model eligibility and product-specific release details.
- Recheck unmanaged or unsupported devices that access CSP-dependent applications.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-693: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-20665 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L3.92.5CISA-ADPVulnerability scoring details
Base CVSS 3.1 score
6.5MediumVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://support.apple.com/en-us/126792CVE reference, apple
- https://support.apple.com/en-us/126793CVE reference, apple
- https://support.apple.com/en-us/126794CVE reference, apple
- https://support.apple.com/en-us/126797CVE reference, apple
- https://support.apple.com/en-us/126798CVE reference, apple
- https://support.apple.com/en-us/126799CVE reference, apple
- https://support.apple.com/en-us/126800CVE reference, apple
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Protection Mechanism Failure
Protection Mechanism Failure represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.