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CVE-2026-68161 (GCVE-0-2026-68161)

Vulnerability from cvelistv5 – Published: 2026-08-10 11:59 – Updated: 2026-08-17 04:59
VLAI
Title
sctp: close UDP tunnel sockets during netns teardown
Summary
In the Linux kernel, the following vulnerability has been resolved: sctp: close UDP tunnel sockets during netns teardown proc_sctp_do_udp_port() starts per-net SCTP UDP tunneling sockets when net.sctp.udp_port is set, and stops/restarts them when the sysctl value changes. The netns exit path does not stop these sockets, so a namespace can be torn down while its SCTP UDP tunnel sockets are still installed. Close the UDP tunnel sockets from sctp_ctrlsock_exit() after unregistering the per-net sysctl table. This prevents new sysctl writes from racing in while the sockets are being released, and closes the sockets before the control socket is destroyed.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 046c052b475e7119b6a30e3483e2888fc606a2f8 , < c6eb2d615210b80339548ab07c0230edaab9a6c7 (git)
Affected: 046c052b475e7119b6a30e3483e2888fc606a2f8 , < 8ff78591d309c50a4fdab683b68dd8d512a270dd (git)
Affected: 046c052b475e7119b6a30e3483e2888fc606a2f8 , < 3bf0e349cbb4f975f35eb22753acc346b89c66a0 (git)
Affected: 046c052b475e7119b6a30e3483e2888fc606a2f8 , < 37ff9794be48d0caa37687e04d09675f9c849121 (git)
Affected: 046c052b475e7119b6a30e3483e2888fc606a2f8 , < ffb2bd7ade36ec4da32c46a6eddbf4515316d08c (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.11
Unaffected: 0 , < 5.11 (semver)
Unaffected: 6.6.151 , ≤ 6.6.* (semver)
Unaffected: 6.12.101 , ≤ 6.12.* (semver)
Unaffected: 6.18.42 , ≤ 6.18.* (semver)
Unaffected: 7.1.6 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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    "redhat_vex": {
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      "cve": "CVE-2026-68161",
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.