CVE-2026-63362

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.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-211-08.json
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://www.o6-automation.com/contact

Configurations

No configuration.

History

30 Jul 2026, 23:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-30 23:16

Updated : 2026-07-31 16:17

NVD link : CVE-2026-63362

Mitre link : CVE-2026-63362

CVE.ORG link : CVE-2026-63362

JSON object : View

Products Affected

No product.

CWE

CWE-191

Integer Underflow (Wrap or Wraparound)

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