CVE-2026-39877
HIGH 7.8A memory corruption issue was addressed with improved memory handling. This issue is fixed in iOS 18.7.10 and iPadOS 18.7.10, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8. An app may be able to disclose kernel memory.
ELEVATED IMPACT
Severe if exploited (CVSS 7.8), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
0.1%chance of exploitation in 30 days · 3rd percentile
○ In CISA KEV
○ Public exploit / PoC
Impact if exploited
7.8CVSS 3.1 · HIGH
- ConfidentialityHigh
- IntegrityHigh
- AvailabilityHigh
What an attacker needs
- ⚠Access: Requires local access to the host
- ✓Privileges: No account or privileges required
- ⚠User interaction: A user must take an action (click / open a file)
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-39877/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-39877/poc.json
Weakness (CWE)
- CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Known Affected Software Configurations
| Vendor | Product | Version range |
|---|---|---|
| Apple | Macos | ≥ 14.0 and < 14.8.8 |
| Apple | Macos | ≥ 15.0 and < 15.7.8 |
All CVSS metrics
- HIGH 7.8 v3.1 · ADP Primary
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - HIGH 7.8 v3.1 · NVD Secondary
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H