CVE-2026-72852 darknet Integer Overflow in Convolutional Layer Buffer Sizing Leads to Heap Buffer Overflow
An integer overflow in darknet's convolutional layer buffer sizing allows heap buffer overflows when processing crafted configuration files, potentially leading to code execution.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-72852?
CVE-2026-72852 is a high-severity vulnerability in hank-ai darknet, published on 20 Aug 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
hank-ai/darknet sizes a convolutional layer's weight and output heap buffers by multiplying configuration fields taken from a .cfg file in unchecked 32-bit int arithmetic. In src-lib/convolutional_layer.cpp, l.nweights is computed as (c / groups) * n * size * size and l.outputs as l.out_h * l.out_w * l.out_c, and both feed xcalloc directly. A .cfg whose true dimension product exceeds INT_MAX wraps to a small or zero value, so the allocation is undersized; for example width and height of 256 with filters of 65536 gives 2^32, which wraps to 0. forward_convolutional_layer then re-derives the GEMM dimensions with a different operand order, computing k as l.size*l.size*l.c / l.groups where the allocation divided before multiplying, and reads and writes through the undersized buffer. Loading the crafted .cfg for inference or training is sufficient and no valid .weights file is required. The reported proof of concept observed a heap buffer overflow read in gemm_nn_fast under AddressSanitizer and glibc allocator metadata corruption in a release build of the same input, indicating an out-of-bounds write.
Which versions are affected by CVE-2026-72852?
How do I fix CVE-2026-72852?
No fix has been published for CVE-2026-72852 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-72852 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-72852 exists.
Sources
Also known as GHSA-5277-mwh4-q4cc.