---
id: CVE-2021-36081
title: >-
  Tesseract OCR 5.0.0-alpha-20201231 has a one_ell_conflict use-after-free
  during a strpbrk call.
summary: >-
  Tesseract OCR 5.0.0-alpha-20201231 has a one_ell_conflict use-after-free
  during a strpbrk call.
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-416
vendor: tesseract-ocr
product: tesseract_ocr
affected:
  - tesseract_ocr = 5.0.0
published: '2021-07-01'
updated: '2026-09-14'
sourceUpdated: '2026-09-14T14:14:21.223'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2021-36081'
references:
  - url: 'https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=29698'
    label: cve@mitre.org
  - url: >-
      https://github.com/google/oss-fuzz-vulns/blob/main/vulns/tesseract-ocr/OSV-2021-211.yaml
    label: cve@mitre.org
  - url: >-
      https://github.com/tesseract-ocr/tesseract/commit/e6f15621c2ab2ecbfabf656942d8ef66f03b2d55
    label: cve@mitre.org
  - url: 'https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=29698'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://github.com/google/oss-fuzz-vulns/blob/main/vulns/tesseract-ocr/OSV-2021-211.yaml
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://github.com/tesseract-ocr/tesseract/commit/e6f15621c2ab2ecbfabf656942d8ef66f03b2d55
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.00887
epssPercentile: 0.57523
ingestedAt: '2026-09-14T14:19:48.712Z'
---

## Overview

Tesseract OCR 5.0.0-alpha-20201231 has a one_ell_conflict use-after-free during a strpbrk call.

## Affected

- `tesseract_ocr = 5.0.0`

## Remediation

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