CVE-2026-63362

MEDIUM

o6 Automation open62541 Integer Underflow

Title source: cna

Description

An unsigned integer underflow in the PubSub signature verification path in open62541 may allow a remote attacker to cause a denial of service via a crafted UDP packet.

References (7)

Core 7

Core References

https://www.o6-automation.com/contact

https://github.com/open62541/open62541/pull/8235/commits/b666d35769ce63998442e4d0810a3fb10b50179f

https://github.com/open62541/open62541/pull/8236/commits/06b99fef667c8ec5bdf0605b4f00c84fcc1d3a60

https://github.com/open62541/open62541/pull/8237/commits/1b71d9c5d9c4d02d4729b8903a52e9f530bf804e

https://github.com/open62541/open62541/pull/8238/commits/afab4107bfd161da9ce8bb30ed77f3968c9c97df

https://www.cisa.gov/news-events/ics-advisories/icsa-26-211-08

https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-211-08.json

View Writeup ZIP pw:eip

Scores

CVSS v3 5.9

Attack Vector NETWORK

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Details

CWE

CWE-191

Status published

Products (4)

o6 Automation/open62541 1.3.0 - 1.3.17

o6 Automation/open62541 1.4.0 - 1.4.16

o6 Automation/open62541 1.5.0 - 1.5.4

o6 Automation/open62541 master

Published Jul 30, 2026

Tracked Since Jul 31, 2026