Is CVE-2026-21887 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-21887 being exploited in the wild.

How severe is CVE-2026-21887?

High severity, with a CVSS score of 7.7, published 22 June 2026.

Which products and versions are affected?

pycti (PyPI) < 6.8.16, ECOSYSTEM:introduced=0,fixed=6.8.16.

Is there a fix for CVE-2026-21887?

Yes. pycti (PyPI): upgrade to 6.8.16 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-21887 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2026-21887?

Check whether you run pycti (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.

CVE-2026-21887: OpenCTI SSRF in Data Ingestion Feature

Q: Which products and versions are affected?

pycti (PyPI) < 6.8.16, ECOSYSTEM:introduced=0,fixed=6.8.16.

Q: Is there a fix for CVE-2026-21887?

Yes. pycti (PyPI): upgrade to 6.8.16 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-21887 attacked?

It is attacked over the network, in a network appliance.

Q: Am I affected by CVE-2026-21887?

Check whether you run pycti (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.

CVE-2026-21887 · Severity: high · CVSS 7.7 · Published 2026-06-22

OpenCTI, a platform for managing cyber threat intelligence, contains a vulnerability in its data ingestion feature. An attacker with basic user permissions can force the platform to send requests to internal systems that are not normally accessible from the internet. This could allow an attacker to steal sensitive configuration data from cloud metadata services or interact with internal databases like Redis and Elasticsearch, potentially leading to a broader compromise of the organization's infrastructure.

Technologies: pycti (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2026-21887 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-21887 being exploited in the wild.
How severe is CVE-2026-21887?: High severity, with a CVSS score of 7.7, published 22 June 2026.
Which products and versions are affected?: pycti (PyPI) < 6.8.16, ECOSYSTEM:introduced=0,fixed=6.8.16.
Is there a fix for CVE-2026-21887?: Yes. pycti (PyPI): upgrade to 6.8.16 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-21887 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-21887?: Check whether you run pycti (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

pycti (PyPI): upgrade to 6.8.16 or later
```
pip install "pycti>=6.8.16"
```

Technical details

A semi-blind Server-Side Request Forgery (SSRF) exists in OpenCTI's data ingestion component. The vulnerability stems from improper input validation of user-supplied URLs and the use of the Axios HTTP client with its default 'allowAbsoluteUrls: true' configuration. A remote attacker with low privileges can provide a crafted absolute URL to force the server to initiate requests to arbitrary internal or external endpoints. This can be used to target internal services (e.g., Redis, Elasticsearch, RabbitMQ) or cloud metadata services (AWS/Azure/GCP) to exfiltrate credentials or configuration details. The issue is addressed in version 6.8.16.

Affected products

Filigran OpenCTI < 6.8.16
Filigran pycti < 6.8.16

Identifiers

CVE-2026-21887
GHSA-ffm6-vvph-g5f5
PYSEC-2026-118

Timeline

2026-03-12: disclosed: NVD publication date
2026-06-22: advisory: GitHub Advisory published

References

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