SB2026081890 - Ubuntu update for linux-oracle

Description

This security bulletin contains information about 36 vulnerabilities.

1) Improper access control (CVE-ID: CVE-2026-31668)

CWE-ID: CWE-284 - Improper Access Control

CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a local user to bypass routing policy restrictions.

The vulnerability exists due to improper access control in the seg6 lwtunnel dst_cache handling when processing input and output paths in different routing contexts. A local user can trigger packet processing through one path so that the other path reuses an incorrect cached destination to bypass routing policy restrictions.

The issue occurs because a single destination cache is shared between seg6_input_core() and seg6_output_core(), even though these paths may perform SID lookup under different routing contexts such as ingress-interface-based rules or VRF table separation.

2) Use-after-free (CVE-ID: CVE-2026-52924)

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 use-after-free in the SCTP outqueue and stream scheduler state handling when processing a stale COOKIE-ECHO condition. A remote attacker can send a stale cookie error during SCTP association handling to cause a denial of service.

The issue occurs when an association is rolled back from COOKIE_ECHOED to COOKIE_WAIT, leaving scheduler state referencing freed stream entries.

3) Integer overflow (CVE-ID: CVE-2026-52914)

CWE-ID: CWE-190 - Integer overflow

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 an integer overflow in the batman-adv fragment reassembly logic when processing malformed fragment chains. A local user can send malformed fragments to cause a denial of service.

4) Out-of-bounds write (CVE-ID: CVE-2026-46331)

CWE-ID: CWE-787 - Out-of-bounds write

CVSSv4: 6.9 [CVSS:4.0/AV:L/AC:L/AT:N/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 an out-of-bounds write in tcf_pedit_act() when processing packet edit actions with typed keys and runtime header offsets. A local user can supply crafted pedit parameters that cause writes to a region that has not been properly copy-on-written to cause memory corruption.

The issue can involve negative offsets such as Ethernet header edits at ingress.

5) Improper input validation (CVE-ID: CVE-2026-46266)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to alter forwarding and path MTU exception handling state.

The vulnerability exists due to improper input validation in RAW socket handling in the IPv4 and IPv6 ICMP error delivery paths when processing malicious incoming ICMP packets with an embedded packet header using protocol 255. A remote attacker can send a specially crafted ICMP packet to alter forwarding and path MTU exception handling state.

Exploitation requires the presence of a RAW socket created with IPPROTO_RAW.

6) Use-after-free (CVE-ID: CVE-2026-43499)

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 use-after-free in remove_waiter() when rolling back a proxy lock from futex_requeue(). A local user can trigger the affected rtmutex slowlock and proxy-lock rollback path to cause a denial of service.

The issue can leave waiter task state uncleared and operate on the wrong top priority waiter task.

7) Improper Check or Handling of Exceptional Conditions (CVE-ID: CVE-2026-43493)

CWE-ID: CWE-703 - Improper Check or Handling of Exceptional Conditions

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 error conditions in the pcrypt crypto subsystem when processing MAY_BACKLOG requests. A local user can trigger requests that return EBUSY to cause a denial of service.

8) Race condition (CVE-ID: CVE-2026-43198)

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CVSSv4: 8.2 [CVSS:4.0/AV:N/AC:L/AT:P/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 race condition in tcp_v6_syn_recv_sock() when handling IPv6 TCP connection requests. A remote attacker can send network traffic that triggers the race to cause a denial of service.

The issue occurs because a child socket may become visible in the TCP ehash table before its IPv6 state is fully initialized.

9) Out-of-bounds read (CVE-ID: CVE-2026-43071)

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 an out-of-bounds read in dentry_hashtable when processing lookups with dhash_entries set to 1. A local user can trigger filesystem lookup operations to cause a denial of service.

The issue occurs because a single hash bucket can cause an invalid shift calculation that leads to access of unallocated memory.

10) Use of Uninitialized Variable (CVE-ID: CVE-2026-52931)

CWE-ID: CWE-457 - Use of Uninitialized Variable

CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to cause undefined behavior.

The vulnerability exists due to use of uninitialized memory in batadv_tp_recv_ack() and batadv_tp_stop() in the tp_meter component when processing a malicious ACK packet for a tp_meter session while the node is acting as a receiver. A remote attacker can send a malicious ACK packet to cause undefined behavior.

The issue occurs when sender-only members are accessed for tp_vars in the BATADV_TP_RECEIVER role during an ongoing tp_meter session.

11) Use-after-free (CVE-ID: CVE-2026-31657)

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 batman-adv BLA claim handling code when processing netlink claim dump operations or checking claims. A local user can trigger concurrent claim updates and reader access to dereference a freed backbone gateway pointer to cause a denial of service.

12) Integer underflow (CVE-ID: CVE-2026-31649)

CWE-ID: CWE-191 - Integer underflow

CVSSv4: 8.4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a local user to disclose sensitive information and cause memory corruption.

The vulnerability exists due to integer underflow in jumbo_frm() chain-mode implementation in the stmmac driver when processing a packet whose linear portion is smaller than the buffer size but whose total length exceeds it due to page fragments. A local user can send a specially crafted packet to disclose sensitive information and cause memory corruption.

On systems without an IOMMU, the issue can cause DMA mappings to reference kernel memory beyond the skb buffer.

13) Improper control of a resource through its lifetime (CVE-ID: CVE-2026-31448)

CWE-ID: CWE-664 - Improper control of a resource through its lifetime

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 state management in ext4_ext_map_blocks() and ext4_xattr_block_set() when handling mkdir or mknod operations after a failed extent insertion. A local user can trigger filesystem operations that leave residual extent metadata to cause a denial of service.

The issue can result in an infinite loop and prolonged blocking while the inode lock is not released.

14) Use-after-free (CVE-ID: CVE-2026-31414)

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 nf_conntrack_expect when dumping the helper name via ctnetlink or /proc. A local user can trigger access to freed conntrack helper state to cause a denial of service.

The issue involves unsafe use of nfct_help() without holding a reference to the master conntrack.

15) Out-of-bounds read (CVE-ID: CVE-2026-31405)

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 execute arbitrary code.

The vulnerability exists due to an out-of-bounds read in handle_one_ule_extension() extension handler tables when processing network-controlled ULE extension header data. A remote attacker can send a specially crafted SNDU with an extension header type value of 255 to execute arbitrary code.

The out-of-bounds value may be dereferenced and called as a function pointer.

16) Use-after-free (CVE-ID: CVE-2024-38612)

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 IS_ENABLED() function in net/ipv6/seg6.c. A local user can escalate privileges on the system.

17) Use-after-free (CVE-ID: CVE-2021-47378)

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 nvme_rdma_free_queue(), nvme_rdma_conn_established(), nvme_rdma_route_resolved() and nvme_rdma_cm_handler() functions in drivers/nvme/host/rdma.c. A local user can escalate privileges on the system.

18) Improper locking (CVE-ID: CVE-2021-47354)

CWE-ID: CWE-667 - Improper Locking

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 perform a denial of service (DoS) attack.

The vulnerability exists due to improper locking within the drm_sched_entity_kill_jobs_cb() function in drivers/gpu/drm/scheduler/sched_entity.c. A local user can perform a denial of service (DoS) attack.

19) Off-by-one (CVE-ID: CVE-2026-53088)

CWE-ID: CWE-193 - Off-by-one Error

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 an off-by-one error in bcmgenet_put_txcb in the bcmgenet network driver when handling transmit control block pointer rewinding. A local user can trigger the flawed pointer handling to cause a denial of service.

20) Insufficient verification of data authenticity (CVE-ID: CVE-2025-27558)

CWE-ID: CWE-345 - Insufficient Verification of Data Authenticity

CVSSv4: 5.3 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows an attacker to perform spoofing attack.

The vulnerability exists due to insufficient verification of data authenticity in mesh networks using Wi-Fi Protected Access (WPA, WPA2, or WPA3) or Wired Equivalent Privacy (WEP). A remote attacker on the local network can inject arbitrary frames towards devices that support receiving non-SSP A-MSDU frames and perform spoofing attack.

21) Use-after-free (CVE-ID: CVE-2026-53359)

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 KVM x86 shadow paging logic when changing a PDE mapping from outside the guest and deleting a memslot. A local user can trigger stale rmap entries and subsequent dereference of a freed sptep to cause a denial of service.

The issue occurs when a modified PDE points to a non-leaf page, causing a role mismatch between reused shadow pages for large 2MB mappings and new 4KB mappings.

22) Out-of-bounds read (CVE-ID: CVE-2026-53309)

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, modify data, or cause a denial of service.

The vulnerability exists due to an out-of-bounds read in dlm_match_regions() when comparing local and remote regions. A remote attacker can trigger the vulnerable region comparison to disclose sensitive information, modify data, or cause a denial of service.

23) Out-of-bounds read (CVE-ID: CVE-2026-53246)

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:L/VA:L/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to disclose sensitive information or cause memory corruption.

The vulnerability exists due to an out-of-bounds read in sctp_unpack_cookie() and cached peer INIT chunk processing when processing a crafted COOKIE_ECHO chunk. A remote attacker can send a specially crafted COOKIE_ECHO chunk with an inflated cached INIT chunk length to disclose sensitive information or cause memory corruption.

The issue occurs in a listening SCTP server while walking parameters from the cached peer INIT chunk embedded after the cookie.

24) Use-after-free (CVE-ID: CVE-2026-53228)

CWE-ID: CWE-416 - Use After Free

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 a use-after-free in the ipip6_tunnel_xmit() function in the SIT IPv6 tunneling implementation when handling GSO packets after offload processing. A local user can trigger transmission of a crafted packet to disclose sensitive information.

The issue occurs because a cached inner IPv6 header pointer may become stale if the skb head is moved during offload handling, and the stale pointer may later be used to read header fields.

25) Out-of-bounds read (CVE-ID: CVE-2026-53225)

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 __sctp_rcv_asconf_lookup() in net/sctp/input.c when processing a truncated trailing ASCONF chunk containing a declared IPv6 address parameter. A remote attacker can send a specially crafted SCTP packet to disclose sensitive information.

The issue is reachable from the no-association lookup path.

26) Out-of-bounds read (CVE-ID: CVE-2026-53224)

CWE-ID: CWE-125 - Out-of-bounds read

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 out-of-bounds read in SCTP cookie processing in sctp_unpack_cookie(), sctp_process_init(), and sctp_raw_to_bind_addrs() when handling a malformed COOKIE_ECHO containing a truncated embedded INIT chunk or malformed address parameters. A remote attacker can send a specially crafted COOKIE_ECHO to cause a denial of service.

When cookie authentication is disabled, an oversized raw address list length can also be used to trigger the out-of-bounds read condition.

27) Out-of-bounds write (CVE-ID: CVE-2026-53176)

CWE-ID: CWE-787 - Out-of-bounds write

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 an out-of-bounds write in isert_login_recv_done() and isert_rx_login_req() in drivers/infiniband/ulp/isert/ib_isert.c when processing a login PDU shorter than ISER_HEADERS_LEN. A remote attacker can send a specially crafted login send work request to cause a denial of service.

The vulnerable code path is reachable during the login phase before iSCSI authentication.

28) Spoofing attack (CVE-ID: CVE-2020-24588)

CWE-ID: CWE-451 - User Interface (UI) Misrepresentation of Critical Information (Clickjacking, spoofing)

CVSSv4: 5.3 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to perform spoofing attack.

The vulnerability exists due to incorrect processing of user-supplied data in Windows Wireless Networking. A remote attacker on the local network can spoof page content.

29) Improper input validation (CVE-ID: CVE-2026-53045)

CWE-ID: CWE-20 - Improper input validation

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 input validation in the tegra124 emc timing change logic when processing memory timing settings. A local user can provide a timing configuration with an incorrect DLL state check to cause a denial of service.

30) Out-of-bounds read (CVE-ID: CVE-2026-53043)

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 dlm_match_regions() when processing a crafted DLM_QUERY_REGION network message. A remote attacker can send a specially crafted network message to disclose sensitive information.

31) Use-after-free (CVE-ID: CVE-2026-53006)

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 icmpv6_rcv() in the IPv6 ICMP handling code when processing ICMPv6 packets. A remote attacker can send a specially crafted ICMPv6 packet to cause a denial of service.

32) Stack-based buffer overflow (CVE-ID: CVE-2026-53002)

CWE-ID: CWE-121 - Stack-based buffer overflow

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 stack-based buffer overflow in the nf_nat_sip netfilter helper when processing crafted SIP/SDP messages. A remote attacker can send specially crafted network traffic to cause a denial of service.

The issue is triggered in mangle_content_len() during SIP message handling.

33) Double free (CVE-ID: CVE-2026-52993)

CWE-ID: CWE-415 - Double 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 double free in tipc_buf_append() when validating a reassembled skb after tipc_msg_validate() reallocates it. A local user can trigger the error-handling path with a crafted TIPC message to cause a denial of service.

34) Out-of-bounds read (CVE-ID: CVE-2026-52986)

CWE-ID: CWE-125 - Out-of-bounds read

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 out-of-bounds read in the nf_conntrack_sip SIP message parser when parsing non-NUL-terminated SIP packet data containing crafted port values. A remote attacker can send a specially crafted SIP packet to cause a denial of service.

The issue involves port parsing in epaddr_len(), ct_sip_parse_header_uri(), and ct_sip_parse_request(), where parsing could reach the buffer limit without a trailing character.

35) Use-after-free (CVE-ID: CVE-2026-52982)

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 rtl8150_start_xmit() when submitting a USB transmit URB and updating transmit statistics. A local user can trigger concurrent URB completion to cause a denial of service.

The issue is caused by reading skb->len after usb_submit_urb() returns, while the skb may already have been freed by the completion path on another CPU in softirq context.

36) Out-of-bounds read (CVE-ID: CVE-2026-52955)

CWE-ID: CWE-125 - Out-of-bounds read

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 an out-of-bounds access in crush_decode() when processing a CEPH_MSG_OSD_MAP message containing a crush map with mismatched bucket algorithm fields. A remote attacker can send a specially crafted CEPH_MSG_OSD_MAP message to cause a denial of service.

Remediation

Install update from vendor's website.

References

• https://ubuntu.com/security/notices/USN-8645-1