SB2026092438 - Red Hat Enterprise Linux 8 update for kernel-rt
Published: September 24, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 5 vulnerabilities.
1) Use-after-free (CVE-ID: CVE-2026-31566)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a use-after-free in amdgpu_amdkfd_submit_ib() when waiting for GPU job completion after submitting a GPU job. A local user can trigger the vulnerable code path to cause a denial of service.
2) Use-after-free (CVE-ID: CVE-2026-52912)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to a use-after-free in nf_queue when reinjecting queued bridge LOCAL_IN packets. A remote attacker can trigger packet queueing and later reinjection to cause a denial of service.
The issue occurs because skb->dev can still reference a freed bridge master device while the packet remains queued.
3) Use-after-free (CVE-ID: CVE-2026-68121)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 5.8 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause memory corruption.
The vulnerability exists due to a use-after-free in pppoe_sendmsg() when handling a blocked send while a non-Ethernet port is added to an empty team device. A local user can trigger skb head reallocation and subsequent writes through a stale PPPoE header pointer to cause memory corruption.
The issue occurs because device header callbacks may reallocate the skb head and invalidate saved pointers into it.
4) Use-after-free (CVE-ID: CVE-2026-80714)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a use-after-free in the ipvs connection handling logic when binding synced connections to a destination. A local user can trigger creation and expiry of a crafted synced connection state to cause a denial of service.
The issue occurs when a synced connection inherits the one-packet flag after it is already hashed, which can leave stale hash nodes pointing to a freed struct ip_vs_conn.
5) Improper Validation of Specified Quantity in Input (CVE-ID: CVE-2026-89480)
CWE-ID: CWE-1284 - Improper Validation of Specified Quantity in Input
CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to disclose sensitive information.
The vulnerability exists due to improper validation of the received data length in the NVMe/TCP host driver when processing a short C2HData PDU from an NVMe/TCP controller. A remote attacker can respond to a read request with fewer bytes than requested to disclose sensitive information.
Remediation
Install update from vendor's website.