SB2026090273 - Red Hat Enterprise Linux 9 update for multiple packages
Published: September 2, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 5 vulnerabilities.
1) Use-after-free (CVE-ID: CVE-2026-23111)
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 escalate privileges on the system.
The vulnerability exists due to a use-after-free error within the nft_map_catchall_activate() function in net/netfilter/nf_tables_api.c. A local user can escalate privileges on the system.
2) Always-Incorrect Control Flow Implementation (CVE-ID: CVE-2026-43114)
CWE-ID: CWE-670 - Always-Incorrect Control Flow Implementation
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 improper handling of stale bits in nft_set_pipapo_avx2 match functions in the netfilter pipapo set implementation when processing crafted set elements during avx2-based matching. A local user can load and reload a crafted pipapo set to cause a denial of service.
The issue occurs with avx2 matching functions and can cause a non-matching expired entry to be treated as a match after a set flush and reload operation.
3) Out-of-bounds read (CVE-ID: CVE-2026-43112)
CWE-ID: CWE-125 - Out-of-bounds read
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 out-of-bounds read in cifs_sanitize_prepath when parsing path strings containing only delimiters or no path content. A local user can supply a crafted path string to cause a denial of service.
The issue can be triggered by an empty string or a string such as "/".
4) Use-after-free (CVE-ID: CVE-2026-46323)
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 skb_gro_receive in the GRO subsystem when merging zerocopy skbs. A local user can trigger GRO processing with zerocopy skbs to cause a denial of service.
The issue occurs when either the source skb or the last skb in the GRO chain is zerocopy and uses managed fragment references.
5) Use-after-free (CVE-ID: CVE-2026-53264)
CWE-ID: CWE-416 - Use After Free
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 a use-after-free in the net/sched action lifecycle handling in act_api when NEWTFILTER and DELFILTER are run concurrently. A local user can trigger concurrent filter operations to cause a denial of service.
The issue arises from a race between action lookup and action deletion under RCU-protected access.
Remediation
Install update from vendor's website.