CVSS 4.0
2.3 lowCVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:NCVE-2026-124758 Integer underflow of the record data length in IODWrite requests
Low (2.3) in rt-labs p-net.
P-Net before 1.0.4 does not check the record data length of an IODWrite request to a non-user record index against the size of the record block header. The 32-bit length is reduced by the header size before it is passed to the record handlers, so a length smaller than the header underflows and the handlers receive a data length of about 65530. The fixed-size reads of the I&M and PDPort handlers can then read past the end of the session buffer. The result of the write is discarded. The attacker must have an established Application Relationship or be able to send in the context of one, and requires ADJACENT network access.
Severity
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: no · Technical impact: partial, assessed 2026-11-13. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-191 Integer Underflow (Wrap or Wraparound)
- Published
- Modified
- Assigned by
- rt-labs (CNA)
- NVD analysis
- Deferred: the NVD does not plan to analyze it
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| RT-Labs P-Net | before 1.0.4 |
History
- The NVD deferred its analysis
Changes since this site first stored the record. The same for every record: /api/public/changes.