Use-After-Free in Tesseract OCR (CVE-2021-36081)
Summary
Vulnerability in Tesseract OCR (CVE-2021-36081). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
Tesseract OCR 5.0.0-alpha-20201231 has a one_ell_conflict use-after-free during a strpbrk call.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A weakness called CVE-2021-36081 was discovered in Tesseract OCR.
In plain terms, it is a use-after-free flaw that often leads to attacker takeover.
Severity is High (CVSS 7.8/10). If exploited, attackers can leak data or disrupt key functionality.
What you should do: update the affected software to the latest version. If unsure, ask your IT team or search the vendor's site for "Tesseract OCR CVE-2021-36081".
CVE-2021-36081 (Tesseract OCR). Severity: High / CVSSv3 7.8. Category: CWE-416.
Response plan:
- Check the vendor advisory for affected versions and the patched release.
- If a vulnerable version is running in production, schedule maintenance (urgency from KEV/CVSS).
- If no patch yet, mitigate via WAF rule, disabling the affected feature, etc.
- Monitor logs / SIEM for known IOC and PoC signatures of this CVE.
PoCs and fix commits: see the 'References' section, MITRE, and NVD.
A weakness (CVE-2021-36081) in Tesseract OCR. In plain words, it is a use-after-free flaw that often leads to attacker takeover.
Target versions of Tesseract OCR (see vendor advisory). If running in production, identify exposure immediately.
Severity: High (CVSS 7.8/10). If exploited, attackers can leak data or disrupt key functionality.
Update to the patched release as listed in the vendor advisory. (Typical mitigation pattern for CWE-416)
If a patch is not yet available, consider disabling the affected feature, applying WAF rules, blocking via network ACLs, or isolating the vulnerable version.
Check version information, scan dependencies via SBOM, and monitor SIEM for IOC and PoC signatures related to this CVE.
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2021-36081 tesseract Fixed in: 5.1.0-1
- Ubuntu UBUNTU-CVE-2021-36081 tesseract
References
- web bugs.chromium.org
- web github.com
- web github.com
- web nvd.nist.gov
- web github.com