SIMATIC Drive Controller CPU 1504D TF: Use After Free
CVE-2023-46156 is a high-severity use after free vulnerability in SIMATIC Drive Controller CPU 1504D TF from Siemens, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version V3.1.0 as the first without the flaw, so updating SIMATIC Drive Controller CPU 1504D TF to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.24% chance of exploitation within 30 days, higher than 70% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update SIMATIC Drive Controller CPU 1504D TF to V3.1.0 or a later version.
- Update SIMATIC Drive Controller CPU 1507D TF to V3.1.0 or a later version.
- Update SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants) to V30.1.0 or a later version.
- Read the advisory on cert-portal.siemens.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
Version data comes from the organisation that assigned the CVE; 35 further products are omitted here. 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
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by CNA (siemens.com).
Official description
Affected devices improperly handle specially crafted packets sent to port 102/tcp. This could allow an attacker to create a denial of service condition. A restart is needed to restore normal operations.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other references
Other vulnerabilities in SIMATIC Drive Controller CPU 1504D TF
- 9.6 Critical severity
- 9.6 Critical severity
- 9.6 Critical severity
- 7.1 High severity
- 9.1 Critical severity
- 9.1 Critical severity
Recent Use After Free vulnerabilities
- 7.5 High severity
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 7.8 High severity
- 7.5 High severity
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