Security readout for executives and security teams
Plain-English summary
CVE-2021-36081 is a memory-safety flaw in an alpha Tesseract OCR build. If an affected OCR service processes untrusted content, the bug could cause instability and potentially broader memory-corruption risk. The provided sources do not include a CVSS score or evidence of exploitation.
Executive priority
Prioritize if the organization exposes Tesseract OCR to customer uploads or automated document intake. For internal-only or non-alpha deployments, urgency is lower but still requires inventory because severity and version mapping are incomplete.
Technical view
Tesseract OCR 5.0.0-alpha-20201231 has a use-after-free in one_ell_conflict during a strpbrk call. The record references an OSS-Fuzz finding and a Tesseract commit, but the bundle does not state affected stable releases, exploitability, or a mapped fixed release.
Likely exposure
Exposure is most likely in systems running Tesseract OCR 5.0.0-alpha-20201231, especially services that OCR user-supplied images, PDFs, or scanned documents. The bundle does not identify other affected versions or downstream products.
Exploitation context
No active exploitation is cited, and the CVE is not listed as KEV in the provided bundle. Evidence comes from OSS-Fuzz and the CVE references, indicating a discovered memory-safety crash condition rather than confirmed real-world abuse.
Researcher notes
Key gaps are CVSS, CWE mapping, affected-version range, and fixed-release mapping. The most defensible statement is limited to Tesseract OCR 5.0.0-alpha-20201231 and the referenced OSS-Fuzz issue and commit.
Mitigation direction
- Inventory Tesseract deployments and identify any 5.0.0-alpha-20201231 usage.
- Review the referenced Tesseract commit and vendor guidance for fixed version mapping.
- Move exposed OCR workloads off affected alpha builds where possible.
- Restrict untrusted document processing until remediation is confirmed.
- Monitor OCR services for crashes or anomalous processing failures.
Validation and detection
- Confirm deployed Tesseract version and build commit.
- Check whether the referenced fix commit is present in the deployed source.
- Identify services accepting untrusted OCR inputs.
- Review crash logs for use-after-free or strpbrk-related failures.
- Validate remediation with safe regression tests, not exploit reproduction.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CVE-2021-36081 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/google/oss-fuzz-vulns/blob/main/vulns/tesseract-ocr/OSV-2021-211.yamlCVE reference · x_refsource_MISC
- https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=29698CVE reference · x_refsource_MISC
- https://github.com/tesseract-ocr/tesseract/commit/e6f15621c2ab2ecbfabf656942d8ef66f03b2d55CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.