CyberSecBulletin
CVE-2023-28831NVD status: Modified

SIMATIC BRAUMAT: Integer Overflow or Wraparound

CVE-2023-28831 is a high-severity integer overflow or wraparound vulnerability in SIMATIC BRAUMAT 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 V8.1 SP1 as the first without the flaw, so updating SIMATIC BRAUMAT to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.13% chance of exploitation within 30 days, higher than 67% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update SIMATIC BRAUMAT to V8.1 SP1 or a later version.
  2. Update SIMATIC Cloud Connect 7 CC712 to V2.2 or a later version.
  3. Update SIMATIC Cloud Connect 7 CC716 to V2.2 or a later version.
  4. Read the advisory on cert-portal.siemens.com for workarounds and exact fixed builds.
  5. 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
SiemensSIMATIC BRAUMATbefore V8.1 SP1V8.1 SP1
SiemensSIMATIC Cloud Connect 7 CC712before V2.2V2.2
SiemensSIMATIC Cloud Connect 7 CC716before V2.2V2.2
SiemensSIMATIC Comfort/Mobile RTall versionsNot stated
SiemensSIMATIC Drive Controller CPU 1504D TFbefore V2.9.7; V3.0.1 up to, but not including, V3.0.3V2.9.7, V3.0.3
SiemensSIMATIC Drive Controller CPU 1507D TFbefore V2.9.7; V3.0.1 up to, but not including, V3.0.3V2.9.7, V3.0.3
SiemensSIMATIC ET 200SP CPU 1510SP F-1 PNbefore V2.9.7; before V3.0.3V2.9.7, V3.0.3
SiemensSIMATIC ET 200SP CPU 1510SP-1 PNbefore V2.9.7; before V3.0.3V2.9.7, V3.0.3
SiemensSIMATIC ET 200SP CPU 1512SP F-1 PNbefore V2.9.7; before V3.0.3V2.9.7, V3.0.3
SiemensSIMATIC ET 200SP CPU 1512SP-1 PNbefore V2.9.7; before V3.0.3V2.9.7, V3.0.3
SiemensSIMATIC ET 200SP CPU 1514SP F-2 PNbefore V3.0.3V3.0.3
SiemensSIMATIC ET 200SP CPU 1514SP-2 PNbefore V3.0.3V3.0.3
SiemensSIMATIC ET 200SP CPU 1514SPT F-2 PNbefore V3.0.3V3.0.3
SiemensSIMATIC ET 200SP CPU 1514SPT-2 PNbefore V3.0.3V3.0.3
SiemensSIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants)before V21.9.7; V30.0.0 up to, but not including, V30.1.0V21.9.7, V30.1.0
SiemensSIMATIC IPC DiagMonitorall versionsNot stated
SiemensSIMATIC NET PC Software V14all versionsNot stated
SiemensSIMATIC NET PC Software V16before V16 Update 8V16 Update 8
SiemensSIMATIC NET PC Software V17before V17 SP1 Update 1V17 SP1 Update 1
SiemensSIMATIC NET PC Software V18before V18 Update 1V18 Update 1
SiemensSIMATIC PCS 7 V9.1before V9.1 SP2 UC08V9.1 SP2 UC08
SiemensSIMATIC PCS neo V4.0all versionsNot stated
SiemensSIMATIC S7-1500 CPU 1511-1 PNbefore V2.9.7; before V3.0.3V2.9.7, V3.0.3
SiemensSIMATIC S7-1500 CPU 1511C-1 PNbefore V2.9.7V2.9.7
SiemensSIMATIC S7-1500 CPU 1511F-1 PNbefore V2.9.7; before V3.0.3V2.9.7, V3.0.3

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 NVD.

Scoring systemScoreSeverityScored by
CVSS 4.08.7HighCNA (siemens.com)
CVSS 3.17.5HighCNA (siemens.com)
CVSS 3.17.5HighNVD

Official description

The OPC UA implementations (ANSI C and C++) in affected products contain an integer overflow vulnerability that could cause the application to run into an infinite loop during certificate validation. This could allow an unauthenticated remote attacker to create a denial of service condition by sending a specially crafted certificate.

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

The underlying weakness: Integer Overflow or Wraparound

The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.

How developers prevent this class of flaw

  • Ensure that all protocols are strictly defined, such that all out-of-bounds behavior can be identified simply, and require strict conformance to the protocol.
  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. If possible, choose a language or compiler that performs automatic bounds checking.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Use libraries or frameworks that make it easier to handle numbers without unexpected consequences. Examples include safe integer handling packages such as SafeInt (C++) or IntegerLib (C or C++).

More Integer Overflow or Wraparound vulnerabilities (CWE-190)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in SIMATIC BRAUMAT

All SIMATIC BRAUMAT vulnerabilities

Recent Integer Overflow or Wraparound vulnerabilities

Spotted an error? Tell us.