sctp: revalidate output stream after association connect wait
When message interleaving is enabled, the first send waits for association
establishment before building its data chunks. The wait drops the socket
lock, and handshake processing can reduce the output stream count to the
peer-advertised inbound stream count. sctp_stream_init() then frees the
extension of every removed stream.
The sender resumes with the stream that it checked before the wait. If the
peer removed that stream, sctp_outq_tail() later dereferences its NULL
extension. Fatal-oops policies then panic the host.
KASAN: null-ptr-deref in range [0x38-0x3f]
RIP: sctp_outq_tail+0x49e/0xaa0
Call Trace:
sctp_primitive_SEND
sctp_sendmsg_to_asoc
sctp_sendmsg
A range check alone is insufficient. Stream reconfiguration can grow the
output count again while the lock is released without recreating extensions
freed by the earlier shrink. The stream can then be in range while its
extension remains NULL. The send-buffer wait has the same issue.
Factor the range and extension checks into a helper and repeat both after
each send-path wait that drops the socket lock. Once the lock is
reacquired, the validation remains stable through data creation and
queueing.
If validation fails after the connect wait, the auto-created association is
already established. Return ESRCH so the existing caller path keeps it
under state-machine ownership instead of freeing it directly, which would
leave protocol, counter and socket state inconsistent.
Analysis and contextual insights are available on OpenCVE Cloud.
No solution or workaround provided in the CVE record.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
Sign in to view the affected projects.
No advisories yet.
Wed, 28 Oct 2026 14:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Linux linux
|
|
| Vendors & Products |
Linux linux
|
Wed, 28 Oct 2026 10:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: sctp: revalidate output stream after association connect wait When message interleaving is enabled, the first send waits for association establishment before building its data chunks. The wait drops the socket lock, and handshake processing can reduce the output stream count to the peer-advertised inbound stream count. sctp_stream_init() then frees the extension of every removed stream. The sender resumes with the stream that it checked before the wait. If the peer removed that stream, sctp_outq_tail() later dereferences its NULL extension. Fatal-oops policies then panic the host. KASAN: null-ptr-deref in range [0x38-0x3f] RIP: sctp_outq_tail+0x49e/0xaa0 Call Trace: sctp_primitive_SEND sctp_sendmsg_to_asoc sctp_sendmsg A range check alone is insufficient. Stream reconfiguration can grow the output count again while the lock is released without recreating extensions freed by the earlier shrink. The stream can then be in range while its extension remains NULL. The send-buffer wait has the same issue. Factor the range and extension checks into a helper and repeat both after each send-path wait that drops the socket lock. Once the lock is reacquired, the validation remains stable through data creation and queueing. If validation fails after the connect wait, the auto-created association is already established. Return ESRCH so the existing caller path keeps it under state-machine ownership instead of freeing it directly, which would leave protocol, counter and socket state inconsistent. | |
| Title | sctp: revalidate output stream after association connect wait | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-10-28T10:35:17.366Z
Reserved: 2026-09-25T10:25:14.398Z
Link: CVE-2026-99165
No data.
Status : Received
Published: 2026-10-28T11:17:36.917
Modified: 2026-10-28T11:17:36.917
Link: CVE-2026-99165
No data.
OpenCVE Enrichment
Updated: 2026-10-28T14:00:17Z
No weakness.