# CVE-2026-77646 — PTC Windchill PDMLink

> As of 2026-08-21, CVE-2026-77646 is a High-severity (band derived from the CVSS v4.0 score, not stated by the CNA) vulnerability in PTC Windchill PDMLink, CVSS v4.0 7.7, EPSS 0.3% (28.1th percentile). No Threadlinqs-tracked threat campaign has been attributed to CVE-2026-77646 as of 2026-08-21; the identifier is re-checked against the Threadlinqs threat corpus on every daily ingest.

**Last updated:** 2026-08-21

## What is CVE-2026-77646?

A Server-Side Request Forgery (SSRF) vulnerability has been reported in PTC Windchill PDMLink and PTC FlexPLM. The vulnerability may be exploited through the deserialization of untrusted data.

The record classifies CVE-2026-77646 under weakness classes [CWE-502](https://intel.threadlinqs.com/cwe/CWE-502), [CWE-918](https://intel.threadlinqs.com/cwe/CWE-918). 2 affected-product entries are recorded, across 1 vendor, listed below. The identifier was first published 46 days ago.

## Severity and exploitation probability

- **CVSS v4.0 base score:** 7.7 — High (derived from score) (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N/AU:Y/R:U/V:D/RE:M/U:Red`)
- **EPSS (FIRST):** 0.3% probability of exploitation in the next 30 days, higher than 28.1% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 5/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-08-20, last modified 2026-08-21

## Is CVE-2026-77646 being exploited?

It currently carries a trending score of 37 in the Threadlinqs vulnerability feed.

## Affected products and versions

- **PTC**: Windchill PDMLink, FlexPLM

## How to fix CVE-2026-77646

No vendor patch reference has been recorded for CVE-2026-77646 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-77646

No threat campaign in the Threadlinqs corpus currently references CVE-2026-77646, 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, NVD, FIRST EPSS. Last verified by Threadlinqs on 2026-08-22. This product uses the NVD API but is not endorsed or certified by the NVD.

**Vendor advisory and patch**

- [ptc.com — vendor advisory](https://www.ptc.com/en/support/article/CS474826)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-77646
Full detection coverage and IOCs for threats exploiting CVE-2026-77646 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp