# CVE-2026-67865

> As of 2026-08-06, CVE-2026-67865 is a HIGH-severity vulnerability, CVSS v3.1 7.5, EPSS 0.2% (16.2th percentile). No Threadlinqs-tracked threat campaign has been attributed to CVE-2026-67865 as of 2026-08-06; the identifier is re-checked against the Threadlinqs threat corpus on every daily ingest.

**Last updated:** 2026-08-06

## What is CVE-2026-67865?

S2OPC 1.7.3 contains an out-of-bounds read in RepublishResponse handling. This allows a remote attacker to cause a denial of service

The record classifies CVE-2026-67865 under weakness class [CWE-125](https://intel.threadlinqs.com/cwe/CWE-125). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on availability. The identifier was first published 61 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 7.5 — HIGH (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **EPSS (FIRST):** 0.2% probability of exploitation in the next 30 days, higher than 16.2% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 6.4/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-08-05, last modified 2026-08-06

## Is CVE-2026-67865 being exploited?

Weaponised exploit code for CVE-2026-67865 is publicly available. 1 public proof-of-concept repository is tracked for this identifier. It currently carries a trending score of 42 in the Threadlinqs vulnerability feed.

- [trickest/cve](https://github.com/trickest/cve/blob/main/2026/CVE-2026-67865.md) (trickest)

## Affected products and versions

No affected-product or package list has been recorded for CVE-2026-67865 in the tracked sources. The vendor advisory and the references below are the authoritative statement of what is affected.

## How to fix CVE-2026-67865

No vendor patch reference has been recorded for CVE-2026-67865 in the tracked sources. Follow the references below for a fix, and treat any affected deployment as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-67865

No threat campaign in the Threadlinqs corpus currently references CVE-2026-67865, in its CVE list or as an indicator. The linkage is recomputed from the live corpus on every daily ingest, so this section fills in as soon as a tracked campaign cites the identifier.

## Sources

Enriched from CVE.org, FIRST EPSS, public proof-of-concept repositories. Last verified by Threadlinqs on 2026-08-06.

**Other references**

- [gitlab.com](https://gitlab.com/systerel/S2OPC/-/work_items/1785)
- [github.com](https://github.com/systerel/S2OPC/blob/S2OPC_Toolkit_1.7.3/src/ClientServer/services/b2c/msg_subscription_publish_bs.c)
- [github.com (msg subscription publish ack bs)](https://github.com/systerel/S2OPC/blob/S2OPC_Toolkit_1.7.3/src/ClientServer/services/b2c/msg_subscription_publish_ack_bs.c)
- [github.com (sopc encoder)](https://github.com/systerel/S2OPC/blob/S2OPC_Toolkit_1.7.3/src/Common/opcua_types/sopc_encoder.c)
- [github.com (CMakeLists)](https://github.com/systerel/S2OPC/blob/S2OPC_Toolkit_1.7.3/tests/ClientServer/CMakeLists.txt)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-67865
Full detection coverage and IOCs for threats exploiting CVE-2026-67865 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp