sctp: clear new_transport when removing a peer
In the Linux kernel, the following vulnerability has been resolved: sctp: clear new_transport when removing a peer sctp_process_asconf_param() stores a newly added peer transport in asoc->new_transport. After all parameters in the ASCONF chunk have been processed, sctp_sf_do_asconf() uses this pointer to send a HEARTBEAT to the new transport. An authenticated ASCONF from a remote SCTP peer can add a transport and remove it again with a wildcard DEL-IP parameter in the same chunk. The wildcard deletion preserves the transport on which the ASCONF arrived, but removes the newly added transport through sctp_assoc_del_nonprimary_peers(). The removal does not clear asoc->new_transport, leaving it pointing to the removed transport. sctp_sf_do_asconf() then creates a HEARTBEAT whose chunk->transport points to the removed transport without holding a transport reference. During local address replacement, src_out_of_asoc_ok keeps this HEARTBEAT on control_chunk_list. After the transport is freed by RCU, a successful ASCONF_ACK for the replacement address releases the queued HEARTBEAT and sctp_outq_select_transport() reads the freed transport's state. The issue was found during a static audit of SCTP objects. With an authenticated peer, the reproducer triggered the same KASAN report in 2 of 2 unpatched runs on a KASAN-enabled netdev/main kernel: BUG: KASAN: slab-use-after-free in sctp_outq_select_transport Read of size 4 at addr ffff88800b9bd95c by task python3/197 Call Trace: sctp_outq_
CVE-2026-74586
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-74586
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6af29ccc223b0feb6fc6112281c3fa3cdb1afddf",
"lessThan": "c0f973bb5118dd1b146cda3fcc8af6f6057befec",
"versionType": "git"
},
{
"status": "affected",
"version": "6af29ccc223b0feb6fc6112281c3fa3cdb1afddf",
"lessThan": "3b539b317cd052236fed0350364ff1268996ba46",
"versionType": "git"
},
{
"status": "affected",
"version": "6af29ccc223b0feb6fc6112281c3fa3cdb1afddf",
"lessThan": "db9d8e3b670f841755bc2018f178472dc6064d27",
"versionType": "git"
},
{
"status": "affected",
"version": "6af29ccc223b0feb6fc6112281c3fa3cdb1afddf",
"lessThan": "31efa656cf6aface26e88f038c14f22ee6ca1500",
"versionType": "git"
},
{
"status": "affected",
"version": "6af29ccc223b0feb6fc6112281c3fa3cdb1afddf",
"lessThan": "291accf36febce751021888de5f15090f4875b56",
"versionType": "git"
},
{
"status": "affected",
"version": "6af29ccc223b0feb6fc6112281c3fa3cdb1afddf",
"lessThan": "ca33df36aa0143a1d04f57d2086020c12e7eddb7",
"versionType": "git"
},
{
"status": "affected",
"version": "6af29ccc223b0feb6fc6112281c3fa3cdb1afddf",
"lessThan": "163847552a571bd55094291f4ffcdc1de0f14a7b",
"versionType": "git"
},
{
"status": "affected",
"version": "6af29ccc223b0feb6fc6112281c3fa3cdb1afddf",
"lessThan": "beb33f8ee1ca83acddb2a5ae80f3d22ec550b4c3",
"versionType": "git"
}
],
"programFiles": [
"net/sctp/associola.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.2"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.2",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.265",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.216",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.183",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.152",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.104",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.45",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.9",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/sctp/associola.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-74586
Source reference:
/cveMetadata/cveId
Publisher severity
critical
Source reference: /containers/cna/metrics
- Event
- #33222 · Revision 1
- Added to Heist Feed
- Publisher date