---
id: CVE-2026-54559
title: PocketSphinx is a small speech recognizer
summary: >-
  PocketSphinx is a small speech recognizer. Prior to 5.1.1, the trie
  language-model loaders in src/lm/ngram_model_trie.c do not adequately validate
  boundary conditions in ARPA, DMP, and binary format headers, and the
  acoustic-model loader…
severity: medium
cvss: 6.9
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N'
cwe:
  - CWE-119
  - CWE-121
  - CWE-122
vendor: cmusphinx
product: pocketsphinx
affected:
  - pocketsphinx < 5.1.1
patched:
  - pocketsphinx 5.1.1
published: '2026-09-14'
updated: '2026-09-15'
sourceUpdated: '2026-09-15T20:17:19.793'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-54559'
references:
  - url: >-
      https://github.com/cmusphinx/pocketsphinx/commit/2a3c03788a9973eff548664334fb781e9f4ad4a5
    label: security-advisories@github.com
  - url: 'https://github.com/cmusphinx/pocketsphinx/releases/tag/v5.1.1'
    label: security-advisories@github.com
  - url: >-
      https://github.com/cmusphinx/pocketsphinx/security/advisories/GHSA-56r5-2p2f-7cxp
    label: security-advisories@github.com
  - url: 'https://github.com/advisories/GHSA-56r5-2p2f-7cxp'
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-54559.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-54559'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-54559'
tags:
  - nvd
  - cve.org
  - ghsa
  - pip
  - csaf
  - vex
  - red-hat
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-15T19:30:28.938576Z'
cvssSource: cna
epss: 0.00548
epssPercentile: 0.43509
aliases:
  - GHSA-56r5-2p2f-7cxp
ecosystem: pip
scores:
  cna: 6.9
  vendor: 6.6
ingestedAt: '2026-07-17T22:16:59.717Z'
---

## Overview

PocketSphinx is a small speech recognizer. Prior to 5.1.1, the trie language-model loaders in src/lm/ngram_model_trie.c do not adequately validate boundary conditions in ARPA, DMP, and binary format headers, and the acoustic-model loaders in src/mdef.c and src/util/bio.c use sscanf with unbounded string fields. Loading an invalid, corrupted, or malicious language or acoustic model can therefore cause stack or heap buffer overflows and memory corruption. An attacker who can write to a directory selected by POCKETSPHINX_PATH can replace or add a model file that PocketSphinx later loads; users of PocketSphinx 5prealpha have no backported patch and must migrate to the fixed release. This issue is fixed in version 5.1.1.

## Remediation

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

## Package advisory (CVE-2026-54559)

Affected packages:

- `pocketsphinx < 5.1.1`

Patched in:

- `pocketsphinx 5.1.1`

Source: https://github.com/advisories/GHSA-56r5-2p2f-7cxp

## Vendor advisories

- **Red Hat VEX** · updated 2026-09-15 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-54559.json)