CyberSecBulletin
CVE-2023-41374NVD status: Modified

Kostac PLC Programming Software: Double Free

CVE-2023-41374 is a high-severity double free vulnerability in Kostac PLC Programming Software from JTEKT ELECTRONICS, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected Kostac PLC Programming Software versions: Version 1.6.11.0 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.2% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Kostac Plc to 1.6.10.0 or a later version.
  2. Read the advisory on electronics.jtekt.co.jp for workarounds and exact fixed builds.
  3. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
JTEKT ELECTRONICSKostac PLC Programming SoftwareVersion 1.6.11.0 and earlierNot stated
JtektKostac Plcbefore 1.6.10.0; 1.6.11.01.6.10.0

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
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
RequiredA user must take an action such as opening a file or link.
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:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. Scored by NVD.

Official description

Double free issue exists in Kostac PLC Programming Software Version 1.6.11.0 and earlier. Arbitrary code may be executed by having a user open a specially crafted project file which was saved using Kostac PLC Programming Software Version 1.6.9.0 and earlier because the issue exists in parsing of KPP project files. The vendor states that Kostac PLC Programming Software Version 1.6.10.0 or later implements the function which prevents a project file alteration. Therefore, to mitigate the impact of these vulnerabilities, a project file which was saved using Kostac PLC Programming Software Version 1.6.9.0 and earlier needs to be saved again using Kostac PLC Programming Software Version 1.6.10.0 or later.

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

The underlying weakness: Double Free

The product calls free() twice on the same memory address.

How developers prevent this class of flaw

  • Choose a language that provides automatic memory management.
  • Ensure that each allocation is freed only once. After freeing a chunk, set the pointer to NULL to ensure the pointer cannot be freed again. In complicated error conditions, be sure that clean-up routines respect the state of allocation properly. If the language is object oriented, ensure that object destructors delete each chunk of memory only once.
  • Use a static analysis tool to find double free instances.

More Double Free vulnerabilities (CWE-415)

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

Third-party and government advisories

Other vulnerabilities in Kostac PLC Programming Software

All Kostac PLC Programming Software vulnerabilities

Recent Double Free vulnerabilities

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