CVE-2026-82358 RT-Labs AB C-Open CANopen SDO Server Write Protection Bypass
An attacker on the CAN bus can bypass write protections to modify read-only Object Dictionary entries in the C-Open library.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-82358?
CVE-2026-82358 is a high-severity missing authorization vulnerability in RT-Labs AB C-Open, published on 1 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
RT-Labs AB C-Open CANopen contains a write protection bypass in the SDO (Service Data Object) server implementation 'src/co_sdo_server.c' that fails to properly validate write permissions when processing download-segment frames. An unauthenticated attacker on the CAN bus can initiate an SDO upload for a read-only Object Dictionary (OD) entry, which sets a data pointer to the read-only object, then send download-segment frames to write to that memory location. The download-segment handler does not verify that a download session is active, allowing any CANopen node to overwrite read-only OD entries using two SDO frames. Note that CANopen protocol operates over CAN bus and does not provide built-in authentication mechanisms. Fixed in 1.1.1.
Weakness: CWE-863
Which versions are affected by CVE-2026-82358?
How do I fix CVE-2026-82358?
No fix has been published for CVE-2026-82358 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-82358 being exploited?
There is no known exploitation of CVE-2026-82358 in the wild and no public exploit code.
Sources
Also known as GHSA-grg4-frf9-pvw5.