Security readout for executives and security teams
Plain-English summary
A malicious disk image can trigger a macOS memory-handling flaw when mounted, potentially crashing the system or corrupting kernel memory. Apple addressed the issue with stronger bounds checking in current security releases. Organizations should prioritize affected Macs that receive external files or routinely mount disk images.
Executive priority
Treat as an urgent patching priority for internet-facing workforces and users handling external files. The kernel-memory impact and critical score justify accelerated deployment, while the absence of cited exploitation supports risk-based emergency scheduling rather than assuming an active incident.
Technical view
CVE-2026-43773 is a CWE-125 out-of-bounds read affecting macOS disk-image handling. Mounting a crafted image may terminate the system or corrupt kernel memory. Apple reports fixes in Sequoia 15.7.8, Sonoma 14.8.8, and Tahoe 26.6. The supplied CVSS 9.8 vector conflicts with the stated mounting prerequisite, warranting validation.
Likely exposure
Macs outside the named fixed releases may require remediation, but the source bundle does not provide reliable vulnerable-version ranges. Exposure is most relevant where users download, receive, or mount untrusted disk images. Inventory macOS editions and versions before determining scope.
Exploitation context
The supplied sources do not report active exploitation, and the CVE is not identified as KEV-listed. Exploitation requires a maliciously crafted disk image to be mounted according to Apple's description. No exploit maturity, observed campaign, or initial-delivery mechanism is established by the bundle.
Researcher notes
The record identifies CWE-125 and kernel-memory corruption but provides no affected component, root-cause detail, complete version range, or exploitation evidence. The CVSS vector states network access and no user interaction, while the description requires mounting a disk image. Analysts should preserve that discrepancy and seek clarification from Apple or the CVE record.
Mitigation direction
- Upgrade Sequoia systems to 15.7.8 or later vendor-approved releases.
- Upgrade Sonoma systems to 14.8.8 or later vendor-approved releases.
- Upgrade Tahoe systems to 26.6 or later vendor-approved releases.
- Discourage mounting disk images from untrusted or unexpected sources.
- Check Apple guidance for unsupported macOS versions and additional mitigations.
Validation and detection
- Inventory macOS edition, version, update status, and business owner.
- Confirm endpoints report Sequoia 15.7.8, Sonoma 14.8.8, or Tahoe 26.6.
- Review update-management failures and isolate systems unable to receive fixes.
- Investigate unexpected terminations associated with recently mounted disk images.
- Verify vendor guidance before treating unlisted macOS versions as unaffected.
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-125: 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-2026-43773 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
- Critical
- CVSS
- 9.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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:H/I:H/A:H3.95.9CISA-ADPVulnerability scoring details
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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/128067CVE reference, apple
- https://support.apple.com/en-us/128071CVE reference, apple
- https://support.apple.com/en-us/128072CVE 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.