CVSS 4.0
7.2 highCVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:NCVE-2026-127122 Out-of-bounds write with too many MCR blocks in a Connect request
High (7.2) in rt-labs p-net.
P-Net before 1.0.4 does not check the number of MCR request blocks in a Connect request against the number of multicast communication relations that an Application Relationship has room for (PNET_MAX_MC_CR, 1 by default). Each further block is written past the end of the array, into the rest of the Application Relationship and, with more blocks, into the following one. The written data comes from the request. No established Application Relationship is needed, and the attacker requires ADJACENT network access. Builds with PNET_OPTION_MC_CR disabled are not affected.
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-787 Out-of-bounds Write
- 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.