CVE-2026-5068
HIGH 7.6A remote, unauthenticated BLE peer can trigger a 2-byte out-of-bounds write in the Bluetooth host during L2CAP LE CoC SDU reassembly. When the application enables segmentation (via chan_ops.alloc_buf) and the chosen RX pool has a user_data_size smaller than 2 bytes, the segmentation counter stored in the net_buf user_data area is written out of bounds in l2cap_chan_le_recv_seg (subsys/bluetooth/host/l2cap.c). The observed effects are an AddressSanitizer abort and, without ASan, heap corruption / fatal error.
Severe if exploited (CVSS 7.6), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
0.5%chance of exploitation in 30 days · 37th percentile
Impact if exploited
7.6CVSS 3.1 · HIGH
- ConfidentialityLow
- IntegrityLow
- AvailabilityHigh
What an attacker needs
- ⚠Access: Must sit on the same / adjacent network
- ✓Privileges: No account or privileges required
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- reference https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-qrcq-hxwj-mqxm
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-5068/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-2026-5068/poc.json
Weakness (CWE)
- CWE-787: Out-of-bounds Write
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
Known Affected Software Configurations
| Vendor | Product | Version range |
|---|---|---|
| Zephyrproject | Zephyr | ≤ 4.4.0 |
All CVSS metrics
- HIGH 7.6 v3.1 · CNA Primary
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H - HIGH 7.6 v3.1 · NVD Secondary
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H - HIGH 8.8 v3.1 · NVD Primary
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H