CyberSecBulletin
CVE-2025-42999Exploited in the wildNVD status: Analyzed

SAP NetWeaver Deserialization

Published Updated By the CyberSecBulletin desk

CVE-2025-42999 is a critical-severity deserialization of untrusted data vulnerability in SAP NetWeaver (Visual Composer development server) from SAP, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. Affected SAP NetWeaver (Visual Composer development server) versions: VCFRAMEWORK 7.50. The record does not name a fixed version, so check the vendor advisory. CISA added it to the Known Exploited Vulnerabilities catalogue on May 15, 2025, which means attacks have been observed in the wild, including in ransomware campaigns.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Check which version of SAP NetWeaver (Visual Composer development server) you run against the affected versions below, and install the vendor's latest release.
  2. CISA's required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
  3. Read the advisory on url.sap for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
SAPSAP NetWeaver (Visual Composer development server)VCFRAMEWORK 7.50Not stated
SAPNetweaver7.5Not 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
LowNo special conditions are needed; the attack works reliably.
Privileges required
HighAdministrator-level access is required first.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
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:L/PR:H/UI:N/S:C/C:H/I:H/A:H. Scored by CNA (sap.com).

Official description

SAP NetWeaver Visual Composer Metadata Uploader is vulnerable when a privileged user can upload untrusted or malicious content which, when deserialized, could potentially lead to a compromise of confidentiality, integrity, and availability of the host system.

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

The underlying weakness: Deserialization of Untrusted Data

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

How developers prevent this class of flaw

  • If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
  • When deserializing data, populate a new object rather than just deserializing. The result is that the data flows through safe input validation and that the functions are safe.
  • Explicitly define a final object() to prevent deserialization.

More Deserialization of Untrusted Data vulnerabilities (CWE-502)

Timeline

  1. CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: total).
  2. CVE record published.
  3. Added to CISA's Known Exploited Vulnerabilities catalogue.
  4. Deadline for US federal agencies to remediate, set by CISA.
  5. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Technical write-ups (may include proof of concept)

Other references

Other vulnerabilities in SAP NetWeaver (Visual Composer development server)

All SAP NetWeaver (Visual Composer development server) vulnerabilities

Recent Deserialization of Untrusted Data vulnerabilities

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