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Vulnerability record · CVE-2021-36081 · published 1 July 2021

CVE-2021-36081: Tesseract-ocr tesseract ocr use after free vulnerability

Tesseract Ocr · Tesseract Ocr

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

7.8 CVSS 3.1 High EPSS 0.89% · top 42.2% CWE-416 · Use after free
7.8CVSS 3.1 base score, v2 6.8
0.89%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
6References, 2 tagged exploit
14 Sep 2026Last modified by NVD

Description

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

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=29698 ExploitIssue TrackingPatchThird Party Advisory
https://github.com/google/oss-fuzz-vulns/blob/main/vulns/tesseract-ocr/OSV-2021-211.yaml Third Party Advisory
https://github.com/tesseract-ocr/tesseract/commit/e6f15621c2ab2ecbfabf656942d8ef66f03b2d55 PatchThird Party Advisory
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=29698 ExploitIssue TrackingPatchThird Party Advisory
https://github.com/google/oss-fuzz-vulns/blob/main/vulns/tesseract-ocr/OSV-2021-211.yaml Third Party Advisory
https://github.com/tesseract-ocr/tesseract/commit/e6f15621c2ab2ecbfabf656942d8ef66f03b2d55 PatchThird Party Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-36081), CISA KEV, FIRST EPSS (scores of 2026-09-28). This page is refreshed as NVD updates the record.