CVE-2026-20664: Apple Safari · Out-of-bounds Write
Affects Apple SafariSource CVE Database V5
Not known to be exploited · CVSS 4.3 Medium : upgrade to 26.4 when convenient.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.7% chance of exploitation in 30 days – higher than 54% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 26.4
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:LExploitation evidence
Disclosed: evidence found.
CVE published 25 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Upgrade Safari and iOS and iPadOS and macOS and visionOS to 26.4.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| AppleSafari | Affected
| Fixed in
|
| AppleiOS and iPadOS | Affected
| Fixed in
|
| ApplemacOS | Affected
| Fixed in
|
| ApplevisionOS | Affected
| Fixed in
|
AI-suggested
This vulnerability has been fixed in Safari 26.4, iOS 26.4, iPadOS 26.4, macOS Tahoe 26.4, and visionOS 26.4 through improved memory handling. Users and administrators should update affected Safari and operating system versions to these fixed releases or later. Red Hat has also released security updates for WebKitGTK+ packages addressing this issue; applying these updates on Red Hat Enterprise Linux 7 Extended Lifecycle Support systems will mitigate the vulnerability. Patch status is confirmed as fixed in these versions.
Description
The issue was addressed with improved memory handling. This issue is fixed in Safari 26.4, iOS 26.4 and iPadOS 26.4, macOS Tahoe 26.4, visionOS 26.4. Processing maliciously crafted web content may lead to an unexpected process crash.
References
- support.apple.com/en-us/126792 (opens in a new tab)
- support.apple.com/en-us/126794 (opens in a new tab)
- support.apple.com/en-us/126799 (opens in a new tab)
- support.apple.com/en-us/126800 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-20664 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2453001 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-20664.json (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:22136 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:10702 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:16056 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:13845 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:11814 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:19535 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:16695 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:14659 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:11329 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:9692 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:19206 (opens in a new tab)