CVE-2026-52909

HIGHPre-NVD 7.87.8—
EchelonGraph scoreHIGH confidence

Score 7.8 from GitHub Security Advisory (severity: HIGH) published 2026-06-19. a secondary CVSS source baseline 7.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
7.8
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.8Exploit: NoneExposed: 0

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

In the Linux kernel, the following vulnerability has been resolved:

ip6_vti: set netns_immutable on the fallback device.

john1988 and Noam Rathaus reported that vti6_init_net() does not set the netns_immutable flag on the per-netns fallback tunnel device (ip6_vti0).

Other similar tunnel drivers (like ip6_tunnel, sit, ip6_gre, and ip_tunnel) correctly set this flag during their fallback device initialization to prevent them from being moved to another network namespace.

CVSS v3
7.8
EG Score
7.8(high)
EPSS
2.2%
KEV
Not listed

Published

June 19, 2026

Last Modified

July 7, 2026

Advisory Details (3)

Auto-updated Jun 28, 2026
No patch confirmed yet.
generic

ip6_vti: set netns_immutable on the fallback device. - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/ecf8904067dcba0dad86ece80874841e60317885
generic

ip6_vti: set netns_immutable on the fallback device. - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/dcdce3bc9f08026ff3739ee7339e1bef526fc5f3
generic

ip6_vti: set netns_immutable on the fallback device. - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d289d5307762d1838aaece22c6b6fcad9e8865f9

Vendor Advisories for CVE-2026-52909(2)

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

Data Freshness Timeline

(refreshed 37× in last 7d / 55× 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. 2026-07-08 00:36 UTCEG score recompute
  2. 2026-07-08 00:36 UTCGHSA enrichment
  3. 2026-07-07 13:46 UTCEPSS rescore
  4. 2026-07-07 13:46 UTCEPSS rescore
  5. 2026-07-07 12:40 UTCEG score recompute
  6. 2026-07-07 12:40 UTCGHSA enrichment
  7. 2026-07-07 00:42 UTCEG score recompute
  8. 2026-07-07 00:42 UTCGHSA enrichment
  9. 2026-07-06 16:27 UTCEPSS rescore
  10. 2026-07-06 16:27 UTCEPSS rescore
  11. 2026-07-06 12:45 UTCEG score recompute
  12. 2026-07-06 12:45 UTCGHSA enrichment
  13. 2026-07-06 02:23 UTCEPSS rescore
  14. 2026-07-06 02:23 UTCEPSS rescore
  15. 2026-07-06 00:43 UTCEG score recompute
  16. 2026-07-06 00:43 UTCGHSA enrichment
  17. 2026-07-05 12:47 UTCEG score recompute
  18. 2026-07-05 12:47 UTCGHSA enrichment
  19. 2026-07-05 02:30 UTCEPSS rescore
  20. 2026-07-05 00:49 UTCEG score recompute
  21. 2026-07-05 00:49 UTCGHSA enrichment
  22. 2026-07-04 12:52 UTCEG score recompute
  23. 2026-07-04 12:52 UTCGHSA enrichment
  24. 2026-07-04 06:31 UTCEPSS rescore
  25. 2026-07-04 00:56 UTCEG score recompute
Show 30 more
  1. 2026-07-04 00:56 UTCGHSA enrichment
  2. 2026-07-03 13:00 UTCEG score recompute
  3. 2026-07-03 13:00 UTCGHSA enrichment
  4. 2026-07-03 00:24 UTCEG score recompute
  5. 2026-07-03 00:24 UTCGHSA enrichment
  6. 2026-07-02 12:27 UTCEG score recompute
  7. 2026-07-02 12:27 UTCGHSA enrichment
  8. 2026-07-02 00:30 UTCEG score recompute
  9. 2026-07-02 00:30 UTCGHSA enrichment
  10. 2026-07-01 15:07 UTCEPSS rescore
  11. 2026-07-01 12:32 UTCEG score recompute
  12. 2026-07-01 12:31 UTCGHSA enrichment
  13. 2026-07-01 00:35 UTCEG score recompute▲ 7.80
  14. 2026-07-01 00:35 UTCGHSA enrichment
  15. 2026-06-30 23:22 UTCEPSS rescore
  16. 2026-06-28 14:07 UTCEPSS rescore
  17. 2026-06-28 07:52 UTCMITRE cvelistV5CVSS v3 → 7.8 · severity → HIGH
  18. 2026-06-28 04:56 UTCEPSS rescore
  19. 2026-06-28 04:56 UTCEPSS rescore
  20. 2026-06-28 04:26 UTCGHSA enrichment
  21. 2026-06-27 03:08 UTCEPSS rescore
  22. 2026-06-25 13:49 UTCEPSS rescore
  23. 2026-06-25 08:16 UTCEG score recompute
  24. 2026-06-25 08:16 UTCGHSA enrichment
  25. 2026-06-24 14:05 UTCEPSS rescore
  26. 2026-06-23 21:33 UTCEPSS rescore
  27. 2026-06-23 21:33 UTCEPSS rescore
  28. 2026-06-22 12:07 UTCGHSA enrichment
  29. 2026-06-19 15:56 UTCEG score recompute
  30. 2026-06-19 15:55 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2026-52909?
CVE-2026-52909 is a high vulnerability published on June 19, 2026. In the Linux kernel, the following vulnerability has been resolved: ip6vti: set netnsimmutable on the fallback device. john1988 and Noam Rathaus reported that vti6initnet() does not set the netnsimmutable flag on the per-netns fallback tunnel device (ip6vti0). Other similar tunnel drivers (like…
When was CVE-2026-52909 disclosed?
CVE-2026-52909 was first published in the National Vulnerability Database on June 19, 2026, with the most recent update on July 7, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-52909 actively exploited?
CVE-2026-52909 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 2.2% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-52909?
CVE-2026-52909 has a CVSS v3 base score of 7.8 (NVD).
How do I remediate CVE-2026-52909?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-52909, 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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