SB2026102838 - Red Hat Enterprise Linux 9 update for multiple packages
Published: October 28, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 5 vulnerabilities.
1) Improper control of a resource through its lifetime (CVE-ID: CVE-2026-53266) Exploited
CWE-ID: CWE-664 - Improper control of a resource through its lifetime
CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/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 improper memory handling in the ebtables SNAT target ARP sender hardware address rewrite in net/bridge/netfilter/ebt_snat.c when processing ARP packets in bridge netfilter hooks. A local user can trigger ARP sender hardware address rewriting on a crafted nonlinear skb to cause a denial of service.
Exploitation requires the ARP sender hardware address rewrite path to be reached with a nonlinear skb fragment backed by a splice-imported file page.
2) 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.
3) Use-after-free (CVE-ID: CVE-2026-74480)
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 br_multicast_leave_group() in the bridge multicast handling code when processing fast-leave operations on port groups. A local user can trigger deletion of a matching port group to cause a denial of service.
The issue can occur when multicast-to-unicast had been enabled, allowing multiple port groups for the same port and group with different source MAC addresses, and is later disabled so entries are matched by port only.
4) Out-of-bounds write (CVE-ID: CVE-2026-74582)
CWE-ID: CWE-787 - Out-of-bounds write
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 an out-of-bounds write.
The vulnerability exists due to an out-of-bounds write in packet_snd() and packet_sendmsg_spkt() in the Linux kernel AF_PACKET implementation when handling non-ring send paths during concurrent device reconfiguration. A local user can send crafted packets while triggering a change in hard_header_len to cause an out-of-bounds write.
The issue affects SOCK_RAW send handling, and packet_sendmsg_spkt() is affected by the same inconsistent header length usage across allocation and packet construction.
5) Improper Validation of Specified Quantity in Input (CVE-ID: CVE-2026-80844)
CWE-ID: CWE-1284 - Improper Validation of Specified Quantity in Input
CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause an out-of-bounds memory access.
The vulnerability exists due to improper validation of routing header segments_left values in ipv6_rearrange_rthdr() when processing raw IPv6 HDRINCL packets with a segments_left value larger than the number of addresses described by hdrlen. A local user can send a crafted packet with an oversized segments_left value to cause an out-of-bounds memory access.
Remediation
Install update from vendor's website.