CVE-2026-43773: An out-of-bounds read was addressed with improved bounds checking
CVE-2026-43773 is a critical-severity flaw (CVSS 9.8) affecting macos. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
An out-of-bounds read was addressed with improved bounds checking. This issue is fixed in macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6. Mounting a maliciously crafted disk image may cause unexpected system termination or corrupt kernel memory.
Why this priority
- Critical severity
- CISA SSVC: automatable with total technical impact
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 9.8 (Critical) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.6% (top 53%) |
| CISA exploited list | No |
| Weakness | CWE-125 |
| Published | 2026-07-27 |
| Last modified | 2026-10-24 |
Last updated 2026-10-24 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Exact fixes by distribution
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-43773?
macos: upgrade to 14.8.8, 15.7.8, 26.6. Exact commands for each OS are on this page.
Is CVE-2026-43773 being exploited?
CVE-2026-43773 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-43773 affect?
CVE-2026-43773 affects macos. Severity is critical (CVSS 9.8). An out-of-bounds read was addressed with improved bounds checking. This issue is fixed in macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6. Mounting a maliciously crafted disk image may cause unexpected system termination or corr
How urgent is CVE-2026-43773?
Priority 54/100. Critical severity; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action
Software pages
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