CVE-2021-21485
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 · uneditedAn unauthorized attacker may be able to entice an administrator to invoke telnet commands of an SAP NetWeaver Application Server for Java that allow the attacker to gain NTLM hashes of a privileged user.
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 confidenceThis vulnerability in SAP NetWeaver Application Server for Java allows an unauthenticated attacker to capture NTLM hashes of privileged users by tricking an administrator into invoking specific telnet commands. The attacker exploits the telnet interface to perform NTLM credential theft, likely through an NTLM relay or man-in-the-middle mechanism.
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= 7.10= 7.20= 7.30= 7.31= 7.40= 7.50CVSS 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
- Low
- Privileges
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/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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Identify the SAP NetWeaver AS Java versionQuery the SAP system for the installed NetWeaver Application Server Java version using SAP management tools or check the system information. Compare this version against the affected list: 7.10, 7.20, 7.30, 7.31, 7.40, 7.50.Affected if The installed version matches any of the affected versions listed.
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Determine if the telnet interface is enabledCheck the SAP NetWeaver AS Java configuration for telnet functionality. Review the Java system properties or configuration files that control the availability of the telnet service.Affected if Telnet interface is active and accessible to network callers.
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Verify if NTLM authentication is in useExamine the authentication configuration of the SAP NetWeaver AS Java system to determine whether NTLM authentication is enabled or configured as an allowed mechanism.Affected if NTLM authentication is enabled or permitted for user authentication.
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Check for exposed telnet portsScan network listeners on common telnet ports or check SAP configuration for registered telnet service endpoints that could be reached by an unauthenticated attacker.Affected if Telnet service is exposed on accessible network ports.
A user is affected if they run an affected version (7.10, 7.20, 7.30, 7.31, 7.40, or 7.50) with the telnet interface enabled and NTLM authentication in use, allowing an attacker to trigger NTLM hash capture through malicious telnet commands.
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.
From vendor dataDisable or restrict telnet functionality in SAP NetWeaver AS for Java if not business-critical, and apply the vendor security patch when released. Consider disabling NTLM authentication and using Kerberos instead.
- Consultation8.0 h
- Implementation16.0 h
- Testing12.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $11,200.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-21485 — 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-2021-21485 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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- 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
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