libfsapfs through 20260921 Heap Out-of-Bounds Read via libfsapfs_key_encrypted_key_read_data
Published Oct 15, 2026 · Updated Nov 3, 2026
Original summary
Normalized public record · Updated Nov 3, 2026
libfsapfs through 20260921 Heap Out-of-Bounds Read via libfsapfs_key_encrypted_key_read_data
Publisher and source text is retained separately from QFinch interpretation.
QFinch assessment
libfsapfs through 20260921 contains an integer underflow in libfsapfs_key_encrypted_key_read_data() that allows attackers to trigger heap out-of-bounds reads via crafted KEK attributes. Attackers can supply a crafted encrypted APFS image with malformed HMAC or wrapped KEK attribute lengths to crash fsapfsinfo, pyfsapfs, dfVFS or plaso and read adjacent heap memory before password checks.
Evidence: public source recordsAffected products
| Affected package, product or range | Fix status |
|---|---|
| Consult the referenced vendor advisory for affected versions. | Consult source advisory |
Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.
Remediation
Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.
- Confirm the affected product and reachable code path exist in your environment.
- Apply the vendor-supported patch or mitigation from the primary advisory.
- Rescan the exact deployed revision and retain verification evidence.
Evidence coverage
- SSVC priority
- LOW
- Confidence
- Not available
- Aliases
- None reported
Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.
Sources and record history
- hackmd.io ↗
- Source repository ↗
- Source repository ↗
- Source repository ↗
- VulnCheck Advisory: libfsapfs through 20260921 Heap Out-of-Bounds Read via libfsapfs_key_encrypted_key_read_data ↗
Record history
Published Oct 15, 2026 · Last refreshed Nov 3, 2026