FKIE_CVE-2026-46227

Vulnerability from fkie_nvd - Published: 2026-05-28 10:16 - Updated: 2026-05-28 13:44
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved: sctp: revalidate list cursor after sctp_sendmsg_to_asoc() in SCTP_SENDALL The SCTP_SENDALL path in sctp_sendmsg() iterates ep->asocs with list_for_each_entry_safe(), which caches the next entry in @tmp before the loop body runs. The body calls sctp_sendmsg_to_asoc(), which may drop the socket lock inside sctp_wait_for_sndbuf(). While the lock is dropped, another thread can SCTP_SOCKOPT_PEELOFF the association cached in @tmp, migrating it to a new endpoint via sctp_sock_migrate() (list_del_init() + list_add_tail() to newep->asocs), and optionally close the new socket which frees the association via kfree_rcu(). The cached @tmp can also be freed by a network ABORT for that association, processed in softirq while the lock is dropped. sctp_wait_for_sndbuf() revalidates @asoc (the current entry) on re-lock via the "sk != asoc->base.sk" and "asoc->base.dead" checks, but nothing revalidates @tmp. After a successful return, the iterator advances to the stale @tmp, yielding either a use-after-free (if the peeled socket was closed) or a list-walk onto the new endpoint's list head (type confusion of &newep->asocs as a struct sctp_association *). Both are reachable from CapEff=0; the type-confusion path gives controlled indirect call via the outqueue.sched->init_sid pointer. Fix by re-deriving @tmp from @asoc after sctp_sendmsg_to_asoc() returns. @asoc is known to still be on ep->asocs at that point: the only callers that list_del an association from ep->asocs are sctp_association_free() (which sets asoc->base.dead) and sctp_assoc_migrate() (which changes asoc->base.sk), and sctp_wait_for_sndbuf() checks both under the lock before any successful return; a tripped check propagates as err < 0 and the loop bails before the re-derive. The SCTP_ABORT path in sctp_sendmsg_check_sflags() returns 0 and the loop hits 'continue' before sctp_sendmsg_to_asoc() is ever called, so the @tmp cached by list_for_each_entry_safe() still covers the lock-held free that ba59fb027307 ("sctp: walk the list of asoc safely") was added for.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/1bfb06ecb00f7fdf35dba8e8f2877346cbe5e078
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/6187a172d6ed57d6b2c327836e4407c6456e639d
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/abb5f36771cc4c05899b34000829a787572a8817
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/bf0f40d8107e2ce827521968dc6926f3e13728ae
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/c9dadb31f36045a8cb65df4bd75e7237ef21a4b5
Impacted products
Vendor Product Version
To clipboard 

{
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsctp: revalidate list cursor after sctp_sendmsg_to_asoc() in SCTP_SENDALL\n\nThe SCTP_SENDALL path in sctp_sendmsg() iterates ep-\u003easocs with\nlist_for_each_entry_safe(), which caches the next entry in @tmp before\nthe loop body runs.  The body calls sctp_sendmsg_to_asoc(), which may\ndrop the socket lock inside sctp_wait_for_sndbuf().\n\nWhile the lock is dropped, another thread can SCTP_SOCKOPT_PEELOFF the\nassociation cached in @tmp, migrating it to a new endpoint via\nsctp_sock_migrate() (list_del_init() + list_add_tail() to\nnewep-\u003easocs), and optionally close the new socket which frees the\nassociation via kfree_rcu().  The cached @tmp can also be freed by a\nnetwork ABORT for that association, processed in softirq while the\nlock is dropped.\n\nsctp_wait_for_sndbuf() revalidates @asoc (the current entry) on re-lock\nvia the \"sk != asoc-\u003ebase.sk\" and \"asoc-\u003ebase.dead\" checks, but nothing\nrevalidates @tmp.  After a successful return, the iterator advances to\nthe stale @tmp, yielding either a use-after-free (if the peeled socket\nwas closed) or a list-walk onto the new endpoint\u0027s list head (type\nconfusion of \u0026newep-\u003easocs as a struct sctp_association *).\n\nBoth are reachable from CapEff=0; the type-confusion path gives\ncontrolled indirect call via the outqueue.sched-\u003einit_sid pointer.\n\nFix by re-deriving @tmp from @asoc after sctp_sendmsg_to_asoc()\nreturns.  @asoc is known to still be on ep-\u003easocs at that point: the\nonly callers that list_del an association from ep-\u003easocs are\nsctp_association_free() (which sets asoc-\u003ebase.dead) and\nsctp_assoc_migrate() (which changes asoc-\u003ebase.sk), and\nsctp_wait_for_sndbuf() checks both under the lock before any\nsuccessful return; a tripped check propagates as err \u003c 0 and the loop\nbails before the re-derive.\n\nThe SCTP_ABORT path in sctp_sendmsg_check_sflags() returns 0 and the\nloop hits \u0027continue\u0027 before sctp_sendmsg_to_asoc() is ever called, so\nthe @tmp cached by list_for_each_entry_safe() still covers the\nlock-held free that ba59fb027307 (\"sctp: walk the list of asoc\nsafely\") was added for."
    }
  ],
  "id": "CVE-2026-46227",
  "lastModified": "2026-05-28T13:44:01.663",
  "metrics": {},
  "published": "2026-05-28T10:16:38.317",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/1bfb06ecb00f7fdf35dba8e8f2877346cbe5e078"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/6187a172d6ed57d6b2c327836e4407c6456e639d"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/abb5f36771cc4c05899b34000829a787572a8817"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/bf0f40d8107e2ce827521968dc6926f3e13728ae"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c9dadb31f36045a8cb65df4bd75e7237ef21a4b5"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Awaiting Analysis"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





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

Author Source Type Date Other

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.