CVE-2025-38679

In the Linux kernel, the following vulnerability has been resolved:

media: venus: Fix OOB read due to missing payload bound check

Currently, The event_seq_changed() handler processes a variable number of properties sent by the firmware. The number of properties is indicated by the firmware and used to iterate over the payload. However, the payload size is not being validated against the actual message length.

This can lead to out-of-bounds memory access if the firmware provides a property count that exceeds the data available in the payload. Such a condition can result in kernel crashes or potential information leaks if memory beyond the buffer is accessed.

Fix this by properly validating the remaining size of the payload before each property access and updating bounds accordingly as properties are parsed.

This ensures that property parsing is safely bounded within the received message buffer and protects against malformed or malicious firmware behavior.

Weakness

The product reads data past the end, or before the beginning, of the intended buffer.

Affected Software

Potential Mitigations

• Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
• When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”
• Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
• To reduce the likelihood of introducing an out-of-bounds read, ensure that you validate and ensure correct calculations for any length argument, buffer size calculation, or offset. Be especially careful of relying on a sentinel (i.e. special character such as NUL) in untrusted inputs.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/540.html

References

• https://git.kernel.org/stable/c/06d6770ff0d8cc8dfd392329a8cc03e2a83e7289
• https://git.kernel.org/stable/c/6f08bfb5805637419902f3d70069fe17a404545b
• https://git.kernel.org/stable/c/8f274e2b05fdae7a53cee83979202b5ecb49035c
• https://git.kernel.org/stable/c/a3eef5847603cd8a4110587907988c3f93c9605a
• https://git.kernel.org/stable/c/bed4921055dd7bb4d2eea2729852ae18cf97a2c6
• https://git.kernel.org/stable/c/c956c3758510b448b3d4d10d1da8230e8c9bf668
• https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html