CyberSecBulletin
CVE-2022-37434NVD status: Modified

SIMATIC S7-1500 CPU 1518-4 PN/DP MFP: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2022-37434 is a critical-severity out-of-bounds write vulnerability in SIMATIC S7-1500 CPU 1518-4 PN/DP MFP from Siemens, with a CVSS 3.1 base score of 9.8 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 V3.1.5 as the first without the flaw, so updating SIMATIC S7-1500 CPU 1518-4 PN/DP MFP to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 19.2% chance of exploitation within 30 days, which is in the top 2.62% of all scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update SIMATIC S7-1500 CPU 1518-4 PN/DP MFP to V3.1.5 or a later version.
  2. Update SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP to V3.1.5 or a later version.
  3. Update SIPLUS S7-1500 CPU 1518-4 PN/DP MFP to V3.1.5 or a later version.
  4. 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 S7-1500 CPU 1518-4 PN/DP MFPV3.1.0 up to, but not including, V3.1.5V3.1.5
SiemensSIMATIC S7-1500 CPU 1518F-4 PN/DP MFPV3.1.0 up to, but not including, V3.1.5V3.1.5
SiemensSIPLUS S7-1500 CPU 1518-4 PN/DP MFPV3.1.0 up to, but not including, V3.1.5V3.1.5
SiemensRUGGEDCOM ROX MX5000before V2.17.0V2.17.0
SiemensRUGGEDCOM ROX MX5000REbefore V2.17.0V2.17.0
SiemensRUGGEDCOM ROX RX1400before V2.17.0V2.17.0
SiemensRUGGEDCOM ROX RX1500before V2.17.0V2.17.0
SiemensRUGGEDCOM ROX RX1501before V2.17.0V2.17.0
SiemensRUGGEDCOM ROX RX1510before V2.17.0V2.17.0
SiemensRUGGEDCOM ROX RX1511before V2.17.0V2.17.0
SiemensRUGGEDCOM ROX RX1512before V2.17.0V2.17.0
SiemensRUGGEDCOM ROX RX1524before V2.17.0V2.17.0
SiemensRUGGEDCOM ROX RX1536before V2.17.0V2.17.0
SiemensRUGGEDCOM ROX RX5000before V2.17.0V2.17.0
ZlibZlib1.2.12 and earlierNot stated
Fedora ProjectFedora35; 36; 37Not stated
DebianDebian Linux10.0Not stated
NetAppActive Iq Unified ManagerNot specified in the recordNot stated
NetAppHciNot specified in the recordNot stated
NetAppManagement Services For Element SoftwareNot specified in the recordNot stated
NetAppOncommand Workflow AutomationNot specified in the recordNot stated
NetAppOntap Select Deploy Administration UtilityNot specified in the recordNot stated
NetAppStoragegridNot specified in the recordNot stated
NetAppHci Compute NodeNot specified in the recordNot stated
NetAppH300s FirmwareNot specified in the recordNot stated

Version data comes from the organisation that assigned the CVE; 7 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
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:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.19.8CriticalNVD
CVSS 3.19.8CriticalCISA (ADP)

Official description

zlib through 1.2.12 has a heap-based buffer over-read or buffer overflow in inflate in inflate.c via a large gzip header extra field. NOTE: only applications that call inflateGetHeader are affected. Some common applications bundle the affected zlib source code but may be unable to call inflateGetHeader (e.g., see the nodejs/node reference).

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

The underlying weakness: Out-of-bounds Write

The product writes data past the end, or before the beginning, of the intended buffer.

How developers prevent this class of flaw

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples include the Safe C String Library (SafeStr) by Messier and Viega, and the Strsafe.h library from Microsoft. These libraries provide safer versions of overflow-prone string-handling functions.
  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND discusses canary-based detection in detail.

More Out-of-bounds Write vulnerabilities (CWE-787)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
  3. 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 vulnerabilities in SIMATIC S7-1500 CPU 1518-4 PN/DP MFP

All SIMATIC S7-1500 CPU 1518-4 PN/DP MFP vulnerabilities

Recent Out-of-bounds Write vulnerabilities

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