GitApplication · Codesys
CVE-2021-34599
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 · uneditedAffected versions of CODESYS Git in Versions prior to V1.1.0.0 lack certificate validation in HTTPS handshakes. CODESYS Git does not implement certificate validation by default, so it does not verify that the server provides a valid and trusted HTTPS certificate. Since the certificate of the server to which the connection is made is not properly verified, the server connection is vulnerable to a man-in-the-middle attack.
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 · moderate confidenceCODESYS Git versions prior to V1.1.0.0 fail to validate HTTPS server certificates during connections, allowing attackers to intercept or modify traffic via man-in-the-middle attacks. The application does not verify certificate authenticity, trusting any server presenting a certificate regardless of validity or trust chain.
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
GitApplication
< 1.1.0.0CVSS 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
- Network
- Complexity
- High
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- None
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
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.
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Verify CODESYS Git is installedLocate the CODESYS Git installation on the system - check common application directories or the program's Add/Remove Programs entryAffected if CODESYS Git is present on the system
-
Determine installed versionFind the version number of the installed CODESYS Git instance - typically accessible via the program's About or Help section, or in the installation directoryAffected if The version cannot be determined or is not visible
-
Compare version to affected rangeCompare the installed version number against the vulnerable range: versions prior to V1.1.0.0Affected if The installed version is less than V1.1.0.0 (for example, V1.0.x, V0.x, or any build prior to 1.1.0.0)
A user is affected if CODESYS Git is installed and the version is lower than V1.1.0.0, as these versions do not validate HTTPS server certificates and are vulnerable to man-in-the-middle attacks.
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 · scoped1.1.0.0
Upgrade to CODESYS Git V1.1.0.0 or later, which implements proper certificate validation. Until upgraded, avoid untrusted networks and consider implementing network-level TLS inspection as a compensating control.
CODESYS Git V1.1.0.0 or later
- 1. Identify the current version of CODESYS Git installed in your environment
- 2. Download CODESYS Git version 1.1.0.0 or later from the official CODESYS download area (customers.codesys.com)
- 3. Review release notes for version 1.1.0.0 to confirm certificate validation has been implemented
- 4. Back up your current CODESYS Git configuration and any repositories
- 5. Install version 1.1.0.0 or newer, following the standard CODESYS installation procedures
- 6. Verify that HTTPS certificate validation is now enabled and functioning
- 7. Test repository connections to confirm secure HTTPS communication is working
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Git
Scoped from the published advisory
- Consultation2.0 h
- Implementation6.0 h
- Testing4.0 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 $3,904.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-34599 — 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-2021-34599 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
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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