How severe is CVE-2026-5068?

CVE-2026-5068 has a CVSS 3.x base score of 7.6, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability high.

Is CVE-2026-5068 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-5068?

CVE-2026-5068 affects Zephyrproject Zephyr. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-5068?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-5068 have an EU (EUVD) identifier?

Yes. CVE-2026-5068 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35353.

When was CVE-2026-5068 published?

CVE-2026-5068 was published on 2026-06-09 and last updated on 2026-07-08.

CVE-2026-5068

CVE-2026-5068 is a high-severity vulnerability in Zephyrproject Zephyr with a CVSS 3.x base score of 7.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Severity: High (CVSS 3.x base score 7.6)
EPSS exploit prediction: 0% (6th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-35353
Weakness: CWE-787
Affected product: Zephyrproject Zephyr
Published: 2026-06-09
Last modified: 2026-07-08

Description

A 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.

Frequently asked questions

What is CVE-2026-5068?: A 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.
How severe is CVE-2026-5068?: CVE-2026-5068 has a CVSS 3.x base score of 7.6, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability high.
Is CVE-2026-5068 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-5068?: CVE-2026-5068 affects Zephyrproject Zephyr. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-5068?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-5068 have an EU (EUVD) identifier?: Yes. CVE-2026-5068 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35353.
When was CVE-2026-5068 published?: CVE-2026-5068 was published on 2026-06-09 and last updated on 2026-07-08.

References

https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-qrcq-hxwj-mqxm

Affected products (1)

cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:*

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