# CVE-2026-76239: stigmem-node has blind SSRF via unvalidated webhook subscription delivery_address

Source: https://junglewise.ai/threats/cve-2026-76239-stigmem-node-has-blind-ssrf-via-unvalidated-webhook-subscription  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-19  
License: CC BY 4.0 with a link back

CVE-2026-76239 · Severity: medium · CVSS 6.3 · Published 2026-08-19

Stigmem before 0.9.0a11 fails to validate the delivery_address parameter when creating webhook subscriptions, allowing authenticated users to specify internal loopback and private network destinations. Attackers can trigger matching fact-change events to cause the Stigmem server to issue server-side HTTP POST requests to internal services, enabling blind SSRF attacks against localhost and private network endpoints.

Technologies: [stigmem-node (PyPI)](https://junglewise.ai/threats/technologies/stigmem-node). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2026-76239 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-76239 being exploited in the wild.

**How severe is CVE-2026-76239?** Medium severity, with a CVSS score of 6.3, published 19 August 2026.

**Which products and versions are affected?** stigmem-node (PyPI) ECOSYSTEM:introduced=0,fixed=0.9.0a11.

**Is there a fix for CVE-2026-76239?** Yes. stigmem-node (PyPI): upgrade to 0.9.0a11 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2026-76239?** Check whether you run stigmem-node (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- stigmem-node (PyPI): upgrade to 0.9.0a11 or later

  ```sh
  pip install "stigmem-node>=0.9.0a11"
  ```


## Affected products

- stigmem-node (PyPI) ECOSYSTEM:introduced=0,fixed=0.9.0a11

## Identifiers

- CVE-2026-76239
- GHSA-5p3m-vhh6-9236

## Related threats

- [stigmem-node: decay sweep expires and counts facts across all tenants (cross-tenant BOLA)](https://junglewise.ai/threats/cve-2026-76238-stigmem-node-decay-sweep-expires-and-counts-facts-across-all)
- [stistigmem-node: quarantine review surface exposes and mutates other tenants' quarantined facts (cross-tenant BOLA)](https://junglewise.ai/threats/cve-2026-76237-stistigmem-node-quarantine-review-surface-exposes-and-mutates)
- [stigmem-node: RTBF tombstones are mis-attributed and suppress reads tenant-blind (cross-tenant BOLA)](https://junglewise.ai/threats/cve-2026-76236-stigmem-node-rtbf-tombstones-are-mis-attributed-and-suppress)
- [stigmem-node's federation peer registration lacked explicit out-of-band approval](https://junglewise.ai/threats/cve-2026-76242-stigmem-node-s-federation-peer-registration-lacked-explicit-out)
- [stigmem-node's unsigned plugin override could be enabled without a second explicit acknowledgment](https://junglewise.ai/threats/cve-2026-76241-stigmem-node-s-unsigned-plugin-override-could-be-enabled-without)