9.8 CRITICAL
- CVSS version (CVSS): 3.1
- Attack Vector (AV): Network (N)
- Attack Complexity (AC): Low (L)
- Privileges Required (PR): None (N)
- User Interaction (UI): None (N)
- Scope (S): Unchanged (U)
- Confidentiality (C): High (H)
- Integrity (I): High (H)
- Availability (A): High (H)
- Modified Attack Vector (MAV): Network (N)
- Modified Attack Complexity (MAC): Low (L)
- Modified Privileges Required (MPR): None (N)
- Modified User Interaction (MUI): None (N)
- Modified Confidentiality (MC): High (H)
- Modified Scope (MS): Unchanged (U)
- Modified Integrity (MI): High (H)
- Modified Availability (MA): High (H)
Activity log
- Created suggestion
Stack buffer overflow in OCPP GetConfiguration key parsing
The OCPP 1.6 client in subsys/net/lib/ocpp/ocpp_j.c contains a stack buffer overflow in parse_getconfig_msg(). When handling a GetConfiguration request from the central system, the handler copied the attacker-controlled JSON "key" string into the caller's fixed 50-byte stack buffer (skey[CISTR50], declared in subsys/net/lib/ocpp/ocpp.c) using an unbounded strcpy(). The parsed key value points directly into the receive buffer, so its length is bounded only by the message size (CONFIG_OCPP_RECV_BUFFER_SIZE, default 2048). The GetConfiguration message is delivered over the WebSocket connection that the charge point opens to its configured central system. The reader thread ocpp_wsreader() reads the message into ui->recv_buf and dispatches it to parse_getconfig_msg() via the PDU function table. An attacker who controls the central system endpoint, or a man-in-the-middle on an unencrypted connection, can send a GetConfiguration request whose "key" field exceeds 50 bytes and overflow the reader thread's stack with attacker-chosen bytes. The consequence is a remotely triggerable stack smash on the OCPP reader thread: at minimum a denial of service, and plausibly remote code execution depending on build-time hardening such as stack canaries and MPU configuration. The fix replaces the strcpy() with a bounded strncpy(key, payload.key[0], CISTR50 - 1) followed by explicit NUL termination, matching the bounded copies already used by the sibling handlers.
References
Affected products
- <4.4.2
Matching in nixpkgs
pkgs.python313Packages.smoke-zephyr
Python utility collection
pkgs.python314Packages.smoke-zephyr
Python utility collection
pkgs.python313Packages.zephyr-python-api
Set of wrappers for Zephyr Scale (TM4J) REST API
pkgs.python314Packages.zephyr-python-api
Set of wrappers for Zephyr Scale (TM4J) REST API
pkgs.python313Packages.zephyr-test-management
Wrappers for both Zephyr Scale and Zephyr Squad (TM4J) REST APIs
Package maintainers
-
@fabaff Fabian Affolter <mail@fabian-affolter.ch>
-
@Steinhagen Viorel-Cătălin Răpițeanu <rapiteanu.catalin@gmail.com>