CVE-2026-21887

HIGHPre-NVD 7.77.7
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.7 under the CNA's CVSS (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 88% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: cna:github_m, epss
7.7
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.7Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

OpenCTI has Semi-Blind SSRF via Unvalidated External URL in Data Ingestion Feature

Summary

The OpenCTI platform’s data ingestion feature accepts user-supplied URLs without validation and uses the Axios HTTP client with its default configuration (allowAbsoluteUrls: true). This allows attackers to craft requests to arbitrary endpoints, including internal services, because Axios will accept and process absolute URLs.

This results in a semi-blind SSRF, as responses may not be fully visible but can still impact internal systems.

Impact

OpenCTI’s data ingestion feature can allow an attacker to make the application send HTTP requests to arbitrary internal or external endpoints. This means an attacker could reach internal services that are not exposed publicly, such as Elasticsearch, Redis, or RabbitMQ, and potentially extract sensitive data or manipulate internal components. In cloud environments, the attacker could target metadata services like AWS, Azure, or GCP to obtain credentials and configuration details, which could lead to full compromise of the infrastructure. Even though the SSRF is semi-blind and the attacker may not see the full response, the ability to interact with internal services can enable enumeration, data exfiltration, and in some cases remote code execution if internal APIs expose dangerous functionality.

CVSS v3
7.7
EG Score
7.7(medium)
EG Risk
EPSS
11.6%
KEV
Not listed

Published

June 22, 2026

Last Modified

June 22, 2026

Vendor Advisories for CVE-2026-21887(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(1 across 1 ecosystem)
PyPI(1)
PackageVulnerable rangeFixed inDependents
pycti1.2.1 ... 6.8.9 (357 versions)6.8.16

Data Freshness Timeline

(refreshed 12× in last 7d / 44× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-22 14:08 UTCEPSS rescore
  2. 2026-07-21 15:24 UTCEPSS rescore
  3. 2026-07-21 15:24 UTCEPSS rescore
  4. 2026-07-20 17:08 UTCEPSS rescore
  5. 2026-07-19 14:31 UTCEPSS rescore
  6. 2026-07-19 14:31 UTCEPSS rescore
  7. 2026-07-19 02:29 UTCEPSS rescore
  8. 2026-07-19 02:28 UTCEPSS rescore
  9. 2026-07-18 10:04 UTCEPSS rescore
  10. 2026-07-18 10:04 UTCEPSS rescore
  11. 2026-07-16 17:03 UTCEPSS rescore
  12. 2026-07-16 17:03 UTCEPSS rescore
  13. 2026-07-15 16:57 UTCEPSS rescore
  14. 2026-07-15 16:57 UTCEPSS rescore
  15. 2026-07-15 02:00 UTCEPSS rescore
  16. 2026-07-15 02:00 UTCEPSS rescore
  17. 2026-07-13 22:30 UTCEPSS rescore
  18. 2026-07-13 06:13 UTCEPSS rescore
  19. 2026-07-13 06:13 UTCEPSS rescore
  20. 2026-07-12 05:46 UTCEPSS rescore
  21. 2026-07-12 05:46 UTCEPSS rescore
  22. 2026-07-11 08:27 UTCEPSS rescore
  23. 2026-07-09 19:10 UTCEPSS rescore
  24. 2026-07-08 15:15 UTCEPSS rescore
  25. 2026-07-08 15:15 UTCEPSS rescore
Show 21 more
  1. 2026-07-07 13:46 UTCEPSS rescore
  2. 2026-07-06 16:27 UTCEPSS rescore
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 02:23 UTCEPSS rescore
  5. 2026-07-06 02:23 UTCEPSS rescore
  6. 2026-07-05 02:30 UTCEPSS rescore
  7. 2026-07-04 06:31 UTCEPSS rescore
  8. 2026-07-04 06:31 UTCEPSS rescore
  9. 2026-07-01 15:06 UTCEPSS rescore
  10. 2026-07-01 15:06 UTCEPSS rescore
  11. 2026-06-30 23:22 UTCEPSS rescore
  12. 2026-06-29 14:06 UTCEPSS rescore
  13. 2026-06-28 14:07 UTCEPSS rescore
  14. 2026-06-28 04:56 UTCEPSS rescore
  15. 2026-06-28 04:56 UTCEPSS rescore
  16. 2026-06-27 03:08 UTCEPSS rescore
  17. 2026-06-25 13:49 UTCEPSS rescore
  18. 2026-06-24 14:05 UTCEPSS rescore
  19. 2026-06-23 21:32 UTCEPSS rescore
  20. 2026-06-22 17:39 UTCEG score recompute
  21. 2026-06-22 17:35 UTCOSV refresh

Frequently asked(5)

What is CVE-2026-21887?
CVE-2026-21887 is a high vulnerability published on June 22, 2026. OpenCTI has Semi-Blind SSRF via Unvalidated External URL in Data Ingestion Feature Summary The OpenCTI platform’s data ingestion feature accepts user-supplied URLs without validation and uses the Axios HTTP client with its default configuration (allowAbsoluteUrls: true). This allows attackers to…
When was CVE-2026-21887 disclosed?
CVE-2026-21887 was first published in the National Vulnerability Database on June 22, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-21887 actively exploited?
CVE-2026-21887 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 11.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-21887?
CVE-2026-21887 has a CVSS v4.0 base score of 7.7 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-21887?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-21887, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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