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CVE-2023-27267NVD status: Modified

Diagnostics Agent (OSCommand Bridge): Missing Authentication for Critical Functionality

CVE-2023-27267 is a high-severity missing authentication for critical functionality vulnerability in Diagnostics Agent (OSCommand Bridge) from SAP, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Diagnostics Agent (OSCommand Bridge) versions: 720. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 14.2% chance of exploitation within 30 days, which is in the top 3.36% of all scored CVEs.

Patch this week

EPSS places it among the vulnerabilities most likely to be exploited soon.

What to do

  1. Check which version of Diagnostics Agent (OSCommand Bridge) you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on sap.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
SAPDiagnostics Agent (OSCommand Bridge)720Not stated
SAPDiagnostics Agent720Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.19.0CriticalCNA (sap.com)
CVSS 3.18.1HighNVD

Official description

Due to missing authentication and insufficient input validation, the OSCommand Bridge of SAP Diagnostics Agent - version 720, allows an attacker with deep knowledge of the system to execute scripts on all connected Diagnostics Agents. On successful exploitation, the attacker can completely compromise confidentiality, integrity and availability of the system.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Missing Authentication for Critical Functionality

The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.

How developers prevent this class of flaw

  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator.
  • When storing data in the cloud (e.g., S3 buckets, Azure blobs, Google Cloud Storage, etc.), use the provider's controls to require strong authentication for users who should be allowed to access the data.

More Missing Authentication for Critical Functionality vulnerabilities (CWE-306)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other references

Recent Missing Authentication for Critical Functionality vulnerabilities

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