---
id: CVE-2026-81334
title: >-
  darknet subscripts its layer array with an index taken from a configuration
  file without checking it against the array's length
summary: >-
  darknet subscripts its layer array with an index taken from a configuration
  file without checking it against the array's length. The array is allocated in
  src-lib/darknet_network.cpp as xcalloc(net.n, sizeof(Darknet::Layer)), sized
  to ex…
severity: medium
cvss: 6.1
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H'
cwe:
  - CWE-125
  - CWE-787
published: '2026-08-27'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T20:43:32.537'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-81334'
references:
  - url: 'https://github.com/hank-ai/darknet'
    label: disclosure@vulncheck.com
  - url: 'https://github.com/hank-ai/darknet/blob/v6.0/src-lib/darknet_cfg.cpp'
    label: disclosure@vulncheck.com
  - url: 'https://github.com/hank-ai/darknet/blob/v6.0/src-lib/darknet_network.cpp'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/darknet-through-6.0-out-of-bounds-read-and-write-via-unchecked-layer-index-in-cfg-parser
    label: disclosure@vulncheck.com
tags:
  - nvd
epss: 0.00172
epssPercentile: 0.05837
ingestedAt: '2026-09-24T20:51:40.236Z'
---

## Overview

darknet subscripts its layer array with an index taken from a configuration file without checking it against the array's length. The array is allocated in src-lib/darknet_network.cpp as xcalloc(net.n, sizeof(Darknet::Layer)), sized to exactly the number of layer sections the file declares. The shortcut, scale_channels and sam sections supply that index through their from field and the route section through its layers field, and parse_shortcut_section in src-lib/darknet_cfg.cpp reads net.layers[index].outputs with no bounds check, which reads past the allocation. The dispatch loop in create_network then reuses the same index to assign net.layers[l.index].use_bin_output and net.layers[l.index].keep_delta_gpu, writing past the allocation at an offset the file controls, with a fixed one-byte value. Parsing a crafted configuration file is sufficient: the parse runs before any weights file is opened and needs no non-default option, so the result is a reliable crash and a write whose location, though not its value, is chosen by whoever supplied the file.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.