Описание
In the Linux kernel, the following vulnerability has been resolved: sctp: auth: verify auth requirement when auth_chunk is NULL sctp_auth_chunk_verify() returns true unconditionally when chunk->auth_chunk is NULL, silently skipping authentication. This is incorrect when:
- skb_clone() failed in the BH receive path, leaving auth_chunk NULL. In sctp_endpoint_bh_rcv() asoc is NULL for new connections, so the early sctp_auth_recv_cid() check cannot catch this.
- No AUTH chunk precedes COOKIE-ECHO, so skb_clone() is never
called and auth_chunk remains NULL.
Fix by checking sctp_auth_recv_cid() when auth_chunk is NULL:
if authentication is required, return false to drop the chunk;
otherwise continue normally.
A flaw was found in the Stream Control Transmission Protocol (SCTP) authentication mechanism within the Linux kernel. Thesctp_auth_chunk_verify()function incorrectly processes authentication chunks, leading to authentication requirements being silently bypassed. This can occur under specific conditions, such as when memory allocation fails or when an authentication chunk is missing before a COOKIE-ECHO message. An attacker could potentially exploit this to bypass intended security controls.
Отчет
A flaw in the Linux kernel Stream Control Transmission Protocol (SCTP) authentication handling, rated MODERATE by Red Hat, affects the kernel and kernel-rt components in Red Hat Enterprise Linux 6 through 10 (including ELS and z-stream update streams) as well as kernel components in Red Hat In-Vehicle OS. The sctp_auth_chunk_verify() function returns true unconditionally when chunk->auth_chunk is NULL, so SCTP authentication requirements can be silently skipped when skb_clone() fails in the bottom-half receive path or when no AUTH chunk precedes a COOKIE-ECHO chunk. Under those conditions, an attacker able to deliver crafted SCTP traffic to a system that enforces SCTP chunk authentication could have unauthenticated chunks processed as authenticated, compromising the integrity of SCTP associations. Red Hat's MODERATE rating reflects the high attack complexity and specific preconditions required for exploitation, which differs meaningfully from the CRITICAL (CVSS 9.8) severity assigned in the upstream CVE record. A fix is being pursued for the affected Red Hat products through the delegated kernel maintenance process.
Меры по смягчению последствий
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Затронутые пакеты
| Платформа | Пакет | Состояние | Рекомендация | Релиз |
|---|---|---|---|---|
| Red Hat Enterprise Linux 6 | kernel | Affected | ||
| Red Hat Enterprise Linux 7 | kernel | Affected | ||
| Red Hat Enterprise Linux 7 | kernel-rt | Affected | ||
| Red Hat Enterprise Linux 9 | kernel-rt | Affected | ||
| Red Hat Enterprise Linux 10 | kernel | Fixed | RHSA-2026:85321 | 19.10.2026 |
| Red Hat Enterprise Linux 8 | kernel-rt | Fixed | RHSA-2026:66324 | 10.09.2026 |
| Red Hat Enterprise Linux 8 | kernel | Fixed | RHSA-2026:66325 | 10.09.2026 |
| Red Hat Enterprise Linux 9 | kernel | Fixed | RHSA-2026:67150 | 14.09.2026 |
| Red Hat Enterprise Linux 9 | kernel | Fixed | RHSA-2026:67150 | 14.09.2026 |
| Shadow Migration Toolkit for Virtualization for RHEL 10 | kernel | Fixed | RHSA-2026:85321 | 19.10.2026 |
Показывать по
Дополнительная информация
Статус:
EPSS
7 High
CVSS3
Связанные уязвимости
In the Linux kernel, the following vulnerability has been resolved: sctp: auth: verify auth requirement when auth_chunk is NULL sctp_auth_chunk_verify() returns true unconditionally when chunk->auth_chunk is NULL, silently skipping authentication. This is incorrect when: 1. skb_clone() failed in the BH receive path, leaving auth_chunk NULL. In sctp_endpoint_bh_rcv() asoc is NULL for new connections, so the early sctp_auth_recv_cid() check cannot catch this. 2. No AUTH chunk precedes COOKIE-ECHO, so skb_clone() is never called and auth_chunk remains NULL. Fix by checking sctp_auth_recv_cid() when auth_chunk is NULL: if authentication is required, return false to drop the chunk; otherwise continue normally.
In the Linux kernel, the following vulnerability has been resolved: sctp: auth: verify auth requirement when auth_chunk is NULL sctp_auth_chunk_verify() returns true unconditionally when chunk->auth_chunk is NULL, silently skipping authentication. This is incorrect when: 1. skb_clone() failed in the BH receive path, leaving auth_chunk NULL. In sctp_endpoint_bh_rcv() asoc is NULL for new connections, so the early sctp_auth_recv_cid() check cannot catch this. 2. No AUTH chunk precedes COOKIE-ECHO, so skb_clone() is never called and auth_chunk remains NULL. Fix by checking sctp_auth_recv_cid() when auth_chunk is NULL: if authentication is required, return false to drop the chunk; otherwise continue normally.
sctp: auth: verify auth requirement when auth_chunk is NULL
In the Linux kernel, the following vulnerability has been resolved: s ...
In the Linux kernel, the following vulnerability has been resolved: sctp: auth: verify auth requirement when auth_chunk is NULL sctp_auth_chunk_verify() returns true unconditionally when chunk->auth_chunk is NULL, silently skipping authentication. This is incorrect when: 1. skb_clone() failed in the BH receive path, leaving auth_chunk NULL. In sctp_endpoint_bh_rcv() asoc is NULL for new connections, so the early sctp_auth_recv_cid() check cannot catch this. 2. No AUTH chunk precedes COOKIE-ECHO, so skb_clone() is never called and auth_chunk remains NULL. Fix by checking sctp_auth_recv_cid() when auth_chunk is NULL: if authentication is required, return false to drop the chunk; otherwise continue normally.
EPSS
7 High
CVSS3