CVE-2026-124758 json
Integer underflow of the record data length in IODWrite requests
published yesterday modified yesterday also EUVD-2026-125298
- cvss
- 2.3
- 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 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.
Patch / fix
- RT-Labs P-Net 1.0.4
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Check with FencerCISA 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 | 2.3 | CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N |
| CNA | 4.0 | 2.3 | CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/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
-
- CWE-191 Integer Underflow (Wrap or Wraparound)
References
Sources
- CVE List CVE-2026-124758
- NVD CVE-2026-124758
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