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Fencer Intel
high 7.2

CVE-2026-127122 json

Out-of-bounds write with too many MCR blocks in a Connect request

published yesterday modified yesterday also EUVD-2026-125302

cvss
7.2
version 4.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 9%
public exploits
0
none known

Summary

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.

Patch / fix

  • RT-Labs P-Net 1.0.4

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
yesterday

Exploit prediction

0.20% chance of exploitation in the next 30 days, higher than 9% of all scored CVEs (FIRST EPSS, 2026-11-14).

CVSS scores

assigned by version score vector
CNA 4.0 7.2 CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N
CNA 4.0 7.2 CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

  • RT-Labs P-Net

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.