CVE-2021-44439
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedA vulnerability has been identified in JT Utilities (All versions < V13.1.1.0), JTTK (All versions < V11.1.1.0). JTTK library in affected products is vulnerable to an out of bounds read past the end of an allocated buffer when parsing specially crafted JT files. An attacker could leverage this vulnerability to leak information in the context of the current process. (ZDI-CAN-14908)
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceThe JTTK library contains an out-of-bounds read vulnerability when parsing specially crafted JT files. Attackers can craft malicious JT files that cause the parser to read past the end of allocated buffers, leaking sensitive memory contents into the process. This information disclosure occurs in the context of the current process, potentially exposing sensitive data to local attackers.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data< 11.1.1.0< 13.1.1.0CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- Low
- Privileges
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Locate JTTK installationSearch for files named 'JtOpen' or 'jttk' in common installation directories such as C:\Program Files\Siemens or /usr/local/siemens, or check if the Jt Open Toolkit library is loaded by your application.Affected if The JTTK library or Siemens JT Utilities software is present on the system.
-
Identify installed JTTK versionCheck the version of the Jt Open Toolkit library file (commonly accessible via file properties or version info). On Windows, right-click the DLL and select Properties > Details to view the File Version. On Linux, use 'strings' or check accompanying version files.Affected if The reported version is below 11.1.1.0.
-
Identify installed JT Utilities versionCheck the version of Siemens JT Utilities installation via the program's About dialog, installed program list, or version file in the installation directory.Affected if The reported version is below 13.1.1.0.
-
Verify JT file parsing is in useDetermine whether any local application or service processes JT files and uses the JTTK library for parsing. Review application dependencies or logs that reference JT parsing functionality.Affected if JT files are being parsed by a vulnerable version of the library.
You are affected if Siemens Jt Open Toolkit version is below 11.1.1.0 or JT Utilities version is below 13.1.1.0, and your system processes JT files using the JTTK library.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped11.1.1.013.1.1.0
Upgrade JT Utilities to version V13.1.1.0 or later and JTTK to version V11.1.1.0 or later. Until patches are applied, exercise caution when opening JT files from untrusted sources.
Jt Open Toolkit 11.1.1.0 and Jt Utilities 13.1.1.0
- Identify the currently installed Jt Open Toolkit (JTTK) and Jt Utilities versions in your environment
- For JTTK: Upgrade to version 11.1.1.0 or later
- For Jt Utilities: Upgrade to version 13.1.1.0 or later
- Verify the upgrade by checking the installed version after patching
- Test that JT file parsing functionality works correctly with the updated version
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation4.0 h
- Testing3.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,088.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-44439 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-44439 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data