Sap KernelApplication · Sap

CVE-2017-16689

HIGH · 8.8 CVSS v3.0 Published 2017-12-12
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
94/100
Remediation priority · Urgent
Remotely reachable Zero-click

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 · unedited
A Trusted RFC connection in SAP KERNEL 32NUC, SAP KERNEL 32Unicode, SAP KERNEL 64NUC, SAP KERNEL 64Unicode 7.21, 7.21EXT, 7.22, 7.22EXT; SAP KERNEL from 7.21 to 7.22, 7.45, 7.49, can be established to a different client or a different user on the same system, although no explicit Trusted/Trusting Relation to the same system has been defined.

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 confidence

SAP Kernel trusted RFC connections can be established to a different client or different user on the same system without an explicit Trusted/Trusting Relation defined. This bypasses the intended access control mechanism in the SAP Kernel, allowing unauthorized RFC calls that should be blocked.

MitigationApply relevant SAP security notes/patches for this kernel vulnerability and audit existing trusted RFC relationships to ensure only intended connections are permitted.

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
Sap KernelApplication
Affected:= 7.21= 7.21ext= 7.22= 7.22ext= 7.45= 7.49

CVSS 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
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.0/AV:N/AC:L/PR:L/UI:N/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 checks

Work through these to decide whether this CVE applies to you.

  1. Check the installed SAP Kernel version
    Execute transaction SM51 or use the SAP kernel version display command (e.g., 'SAPCAR -tvf <kernel_archive>' or check the 'exe' directory for the kernel version file) to determine the exact kernel release and patch level
    Affected if The kernel version matches 7.21, 7.21ext, 7.22, 7.22ext, 7.45, or 7.49 (exact match)
  2. Identify configured RFC destinations
    Execute transaction SM59 to display all defined RFC destinations. Review the list for any RFC connections that use the 'Trusted' or 'Trusting' connection type
    Affected if Any RFC destinations of type 'Trusted RFC' exist in the system
  3. Review existing trusted relationships
    Use transaction RFCTEST or check the trusted system configuration (typically via transaction SMT1 or system profile parameters rfc/trust_rfc_with_logon_check) to list all established trusted relationships between clients
    Affected if Trusted RFC relationships are defined between different clients or users in the system
  4. Audit recent RFC activity logs
    Check system logs (transaction SM37 or STAT trace) and security audit log (transaction SM20) for RFC calls that may have been executed across clients without proper trusted relationship configuration
    Affected if RFC activity is observed between clients where no explicit trusted relationship was intended or documented

A system is affected if it runs a matching vulnerable kernel version AND has any trusted RFC destinations or relationships configured that could be exploited to bypass access controls.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply relevant SAP security notes/patches for this kernel vulnerability and audit existing trusted RFC relationships to ensure only intended connections are permitted.

Fix this in Sap Kernel Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,860
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2017-16689 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2017-16689 in production — separate from our analysis above.

No notes yet

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What this is

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.

What belongs here
  • 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