usb: gadget: f_ncm: validate datagram bounds in ncm_unwrap_ntb()
Key facts
- Attack vector
- —
- Privileges required
- —
- User interaction
- —
- Attack complexity
- —
- Impact type
- —
- Confidentiality · integrity · availability
- —
- Fix status
- Partial Red Hat: 1 without a fix
No CVSS vector from any source. Fix status from CNA and Red Hat.
Summary
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_ncm: validate datagram bounds in ncm_unwrap_ntb() When unpacking host-supplied NTBs, ncm_unwrap_ntb() checks datagram length against frame_max but does not verify that the datagram fits within the declared block length. Additionally, when decoding multiple NTBs from a single socket buffer, subsequent block lengths are not checked against the actual remaining buffer data. With these checks missing, a malicious USB host can specify datagram offsets and lengths that point beyond the block, or supply secondary NTB headers declaring lengths larger than the buffer. skb_put_data() then copies adjacent kernel memory from skb_shared_info into the network skb. Fix this by verifying that sufficient buffer space remains for the NTB header before parsing, handling zero-length block declarations, ensuring that block lengths never exceed the remaining buffer space, and verifying that each datagram payload stays strictly within the block boundary.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 4.9.235 to before 4.10; 4.14.196 to before 4.15; 4.19.143 to before 4.20; 5.4.62 to before 5.5; 5.8.6 to before 5.9; 4.14.328 to before 4.15; 4.19.297 to before 4.20; 5.4.259 to before 5.5 | 4.10, 4.15, 4.20, 5.5, 5.9 | Patch available | CNA |
| Linux | Linux | 5.9 and later | 5.10.265, 5.15.216, 6.1.183, 6.6.148, 6.12.101, 6.18.42, 7.1.6, 7.2 | Patch available | CNA |
- Linux VendorLinux Affected 4.9.235 to before 4.10; 4.14.196 to before 4.15; 4.19.143 to before 4.20; 5.4.62 to before 5.5; 5.8.6 to before 5.9; 4.14.328 to before 4.15; 4.19.297 to before 4.20; 5.4.259 to before 5.5 Fixed in 4.10, 4.15, 4.20, 5.5, 5.9 Patch available CNA
- Linux VendorLinux Affected 5.9 and later Fixed in 5.10.265, 5.15.216, 6.1.183, 6.6.148, 6.12.101, 6.18.42, 7.1.6, 7.2 Patch available CNA
Remediation
- Fix · CNA Linux (Linux) Fixed in 4.10, 4.15, 4.20, 5.5, 5.9
- Fix · CNA Linux (Linux) Fixed in 5.10.265, 5.15.216, 6.1.183, 6.6.148, 6.12.101, 6.18.42, 7.1.6, 7.2
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet |
Not affected: 7 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat Enterprise Linux for NVIDIA 26
- Red Hat OpenShift Container Platform 4
- Red Hat OpenShift Container Platform 5
Timeline
- 2026-10-02 Threatist record created from CVE-2026-68368
- 2026-10-03 Alias added: GHSA-jmw8-f562-3f2g
- 2026-10-30 Affected versions changed · Red Hat
- 2026-11-06 CVSS score changed · Red Hat
- 2026-11-06 CISA SSVC decision points changed
References
Other 8
- https://git.kernel.org/stable/c/35d15bbaec0557330e774ec31412ef508de6e0e0
- https://git.kernel.org/stable/c/6b2be489eaa6293e60549005d91f15ceb150510f
- https://git.kernel.org/stable/c/f87ed889f0f7417b8938c98d8833f559b755373c
- https://git.kernel.org/stable/c/e07751d0527ccc2a1c32eb0b0b7da3b4b9b5381f
- https://git.kernel.org/stable/c/fff1059d139ef798bab917990524faaf25854ca8
- https://git.kernel.org/stable/c/40c706a0224bde194667e3378c689b542fec4b44
- https://git.kernel.org/stable/c/41fd5f2fb0027d3773ae949e3247c2e0a2a7fe5c
- https://git.kernel.org/stable/c/1febec7e47cdcd01f43fb0211094e3010474666e
More Linux vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
Sources
- CVE-2026-68368 · CVE Program
- CVE-2026-68368 · NVD
- FIRST EPSS
- GHSA-jmw8-f562-3f2g · GitHub Advisory Database · CC BY 4.0
- CVE-2026-68368 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences