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The vulnerability occurs in the `mnl::cb_run` function within the mnl Rust library, designed for Netlink message processing. Netlink facilitates kernel-user space communication via socket messages. The function is marked as safe but internally uses unsafe operations without proper bounds checking. When passed a crafted byte slice, it fails to validate the buffer structure before parsing. Netlink messages consist of a header with length fields and payload data. The function reads these headers and assumes the indicated lengths are within buffer bounds. An attacker can provide a malicious buffer where the header specifies a payload length exceeding the actual buffer size. This causes the function to perform out-of-bounds memory reads when accessing the purported payload. Additionally, if the buffer contains malformed nested attributes or invalid pointers, the function may dereference these without validation. This leads to segmentation faults when accessing unmapped memory, resulting in Denial of Service. The unsound behavior violates Rust’s memory safety guarantees, as the safe function annotation misleads developers into trusting it with untrusted input. Exploitation requires calling the function with a malicious buffer, which could be achieved remotely if the application processes Netlink messages from untrusted networks. The issue stems from inadequate validation in unsafe code blocks that handle pointer arithmetic and buffer traversal.
Platform: mnl
Version: Unspecified
Vulnerability: Memory corruption
Severity: Low
date: 2026-01-09
Prediction: 2026-01-30
What Undercode Say:
Showing bash commands and codes related to the blog
Bash command to inspect installed versions:
`cargo tree | grep mnl`
Code snippet demonstrating vulnerable usage:
let data: &[bash] = untrusted_source; mnl::cb_run(data, |_| Ok(()));
how Exploit:
Craft malicious Netlink buffer with invalid length fields. Call `mnl::cb_run` with this buffer. Trigger out-of-bounds read or segmentation fault.
Protection from this CVE
Update to patched version. Validate input buffers. Use sanitizers during testing.
Impact:
Denial of Service. Potential memory disclosure.
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Sources:
Reported By: github.com
Extra Source Hub:
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