SB2026102010 - Red Hat Enterprise Linux 8 update for kernel-rt
Published: October 20, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 10 vulnerabilities.
1) Out-of-bounds read (CVE-ID: CVE-2026-52935)
CWE-ID: CWE-125 - Out-of-bounds read
CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a local user to disclose sensitive information.
The vulnerability exists due to an out-of-bounds read in espintcp_sendmsg() when handling a new send while a previous partial send is still in progress. A local user can trigger a partial send and initiate another send to disclose sensitive information.
The issue occurs in the send path because a stale offset from a live partial-send state can remain attached to a new sk_msg.
2) Heap-based buffer overflow (CVE-ID: CVE-2026-53196)
CWE-ID: CWE-122 - Heap-based Buffer Overflow
CVSSv4: 5.1 [CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows an attacker with physical access to cause a denial of service or execute arbitrary code.
The vulnerability exists due to a heap-based buffer overflow in get_manuf_info() in the io_ti USB serial driver when processing a crafted USB device EEPROM descriptor. An attacker with physical access can connect a malicious USB device with a forged Size field to trigger the overflow and cause a denial of service or execute arbitrary code.
The out-of-bounds access is compounded because a checksum routine also iterates over the device-controlled length after the EEPROM data is read.
3) Use-after-free (CVE-ID: CVE-2026-74588)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote user to cause a denial of service.
The vulnerability exists due to a use-after-free in __sctp_outq_flush_rtx() and SCTP transport tracking when processing SCTP SACKs after transport removal. A remote user can send crafted SCTP control traffic to cause a denial of service.
Exploitation requires an SCTP association peer to trigger transport removal through ASCONF Delete-IP and then send a SACK that reneges on the TSN.
4) Out-of-bounds read (CVE-ID: CVE-2026-74752)
CWE-ID: CWE-125 - Out-of-bounds read
CVSSv4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to disclose sensitive information.
The vulnerability exists due to an out-of-bounds read in SCTP COOKIE_ECHO handling when processing peer-controlled cookie AUTH fields with cookie authentication disabled. A remote attacker can send a forged cookie with a crafted RANDOM length to disclose sensitive information.
The issue is reachable when cookie authentication is disabled, and malformed AUTH parameters restored from the cookie are not validated against local backing arrays.
5) Out-of-bounds write (CVE-ID: CVE-2026-74752)
CWE-ID: CWE-787 - Out-of-bounds write
CVSSv4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to execute arbitrary code.
The vulnerability exists due to an out-of-bounds write in SCTP COOKIE_ECHO handling when processing peer-controlled cookie AUTH fields with cookie authentication disabled. A remote attacker can send a forged cookie with a crafted HMAC identifier to execute arbitrary code.
The issue is reachable when cookie authentication is disabled, and malformed AUTH parameters restored from the cookie are not validated against local backing arrays.
6) Out-of-bounds read (CVE-ID: CVE-2026-89631)
CWE-ID: CWE-125 - Out-of-bounds read
CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/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 an out-of-bounds read in the CIFSTCon() SMB client tree connect response parser when processing a tree connect response with a byte count smaller than two. A remote attacker can send a malformed tree connect response to disclose sensitive information.
Disclosed bytes are exposed through /proc/fs/cifs/DebugData.
7) Use-after-free (CVE-ID: CVE-2026-89479)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 0 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to access freed memory.
The vulnerability exists due to use-after-free in the SCTP endpoint receive loop when processing a specially crafted SCTP packet containing bundled chunks. A remote attacker can send an SCTP packet that deletes an association before subsequent chunks are processed to access freed memory.
Exploitation requires the packet to be processed from the socket backlog in task context.
8) Use-after-free (CVE-ID: CVE-2026-93817)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 0 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a local user to trigger a use-after-free condition.
The vulnerability exists due to improper lifetime management in event::addr_filter_ranges when address-filter ranges are accessed under RCU. A local user can cause address-filter ranges to be freed while they remain accessible under RCU to trigger a use-after-free condition.
9) Use-after-free (CVE-ID: CVE-2026-93288)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 0 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a local user to trigger a use-after-free.
The vulnerability exists due to failure to wait for an RCU grace period in nfnetlink_log per-network state when processing packets concurrently with network namespace teardown. A local user can trigger concurrent packet processing and network namespace teardown to trigger a use-after-free.
10) Use-after-free (CVE-ID: CVE-2026-98320)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to compromise confidentiality, integrity, and availability.
The vulnerability exists due to use-after-free in the netfilter flowtable component when the flowtable datapath accesses connection-tracking state after its reference has been released. A local user can access prematurely released connection-tracking state to compromise confidentiality, integrity, and availability.
RCU typesafe semantics also allow a flowtable datapath reference to resolve to the wrong connection-tracking object.
Remediation
Install update from vendor's website.