CVE-2026-12539

MEDIUMPre-NVD 5.75.7—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 5.7 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.1%, top 99% 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: epss, secondary
5.7
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 5.7Exploit: NoneExposed: 0

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

Docker Sandboxes (sbx) blocks ICMP egress with an authorizer applied only at network-creation time, and does not re-apply it to networks rebuilt from disk when the Docker daemon restarts, so a restart-surviving sandbox forwards ICMP to arbitrary hosts. A workload inside a sandbox, which the threat model treats as untrusted, can therefore defeat the documented ICMP egress block to perform network reconnaissance and exfiltrate data over an ICMP covert channel, regardless of the configured allowlist.

CVSS v3
5.7
EG Score
5.7(medium)
EPSS
0.9%
KEV
Not listed

Published

June 18, 2026

Last Modified

June 30, 2026

Advisory Details (2)

Auto-updated Jun 19, 2026
Patch available. Sources: github_release.
github_release Patch Available

v0.33.0

Patch available: docker/sbx-releases v0.33.0

https://github.com/docker/sbx-releases/releases/tag/v0.33.0
generic

Docker Sandboxes | Docker Docs

https://docs.docker.com/ai/sandboxes/

Vendor Advisories for CVE-2026-12539(1)

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

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 6× in last 7d / 52× 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. 2026-07-20 17:08 UTCEPSS rescore
  3. 2026-07-19 14:30 UTCEPSS rescore
  4. 2026-07-19 02:28 UTCEPSS rescore
  5. 2026-07-16 21:03 UTCGHSA enrichment
  6. 2026-07-16 17:02 UTCEPSS rescore
  7. 2026-07-15 18:18 UTCGHSA enrichment
  8. 2026-07-15 16:57 UTCEPSS rescore
  9. 2026-07-15 02:00 UTCEPSS rescore
  10. 2026-07-14 19:42 UTCGHSA enrichment
  11. 2026-07-13 22:30 UTCEPSS rescore
  12. 2026-07-13 21:01 UTCGHSA enrichment
  13. 2026-07-13 06:12 UTCEPSS rescore
  14. 2026-07-12 22:40 UTCGHSA enrichment
  15. 2026-07-12 05:46 UTCEPSS rescore
  16. 2026-07-12 00:21 UTCGHSA enrichment
  17. 2026-07-11 02:00 UTCGHSA enrichment
  18. 2026-07-10 03:15 UTCGHSA enrichment
  19. 2026-07-09 19:10 UTCEPSS rescore
  20. 2026-07-09 04:55 UTCGHSA enrichment
  21. 2026-07-08 15:15 UTCEPSS rescore
  22. 2026-07-08 15:15 UTCEPSS rescore
  23. 2026-07-08 06:34 UTCGHSA enrichment
  24. 2026-07-07 13:46 UTCEPSS rescore
  25. 2026-07-07 08:15 UTCGHSA enrichment
Show 36 more
  1. 2026-07-06 09:56 UTCGHSA enrichment
  2. 2026-07-06 02:23 UTCEPSS rescore
  3. 2026-07-05 11:31 UTCGHSA enrichment
  4. 2026-07-04 13:12 UTCGHSA enrichment
  5. 2026-07-04 06:31 UTCEPSS rescore
  6. 2026-07-03 14:52 UTCGHSA enrichment
  7. 2026-07-02 16:33 UTCGHSA enrichment
  8. 2026-07-01 18:14 UTCGHSA enrichment
  9. 2026-07-01 15:06 UTCEPSS rescore
  10. 2026-07-01 15:06 UTCEPSS rescore
  11. 2026-06-30 19:55 UTCGHSA enrichment
  12. 2026-06-29 21:36 UTCGHSA enrichment
  13. 2026-06-29 14:06 UTCEPSS rescore
  14. 2026-06-28 23:17 UTCGHSA enrichment
  15. 2026-06-28 14:07 UTCEPSS rescore
  16. 2026-06-28 04:56 UTCEPSS rescore
  17. 2026-06-28 04:56 UTCEPSS rescore
  18. 2026-06-28 00:56 UTCGHSA enrichment
  19. 2026-06-27 03:08 UTCEPSS rescore
  20. 2026-06-27 02:37 UTCGHSA enrichment
  21. 2026-06-26 04:19 UTCGHSA enrichment
  22. 2026-06-25 13:49 UTCEPSS rescore
  23. 2026-06-25 06:00 UTCGHSA enrichment
  24. 2026-06-24 14:05 UTCEPSS rescore
  25. 2026-06-24 07:41 UTCGHSA enrichment
  26. 2026-06-23 21:32 UTCEPSS rescore
  27. 2026-06-23 09:14 UTCGHSA enrichment
  28. 2026-06-22 10:49 UTCGHSA enrichment
  29. 2026-06-21 12:25 UTCGHSA enrichment
  30. 2026-06-20 14:03 UTCGHSA enrichment
  31. 2026-06-19 15:42 UTCGHSA enrichment
  32. 2026-06-18 17:24 UTCEG score recompute▲ 5.70
  33. 2026-06-18 17:24 UTCGHSA enrichment
  34. 2026-06-18 17:22 UTCNVD updateCVSS v3 → 5.7 · CVSS v4 → 5.7
  35. 2026-06-18 15:45 UTCEG score recompute
  36. 2026-06-18 15:45 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2026-12539?
CVE-2026-12539 is a medium vulnerability published on June 18, 2026. Docker Sandboxes (sbx) blocks ICMP egress with an authorizer applied only at network-creation time, and does not re-apply it to networks rebuilt from disk when the Docker daemon restarts, so a restart-surviving sandbox forwards ICMP to arbitrary hosts. A workload inside a sandbox, which the threat…
When was CVE-2026-12539 disclosed?
CVE-2026-12539 was first published in the National Vulnerability Database on June 18, 2026, with the most recent update on June 30, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-12539 actively exploited?
CVE-2026-12539 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-12539?
CVE-2026-12539 has a CVSS v3 base score of 5.7 (NVD).
How do I remediate CVE-2026-12539?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-12539, 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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