{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2025-21707 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-21707 is a critical memory corruption vulnerability in Linux kernel, published on 27 Feb 2025. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2025-21707 and fix it if it is affected.\n\nWhat it is: CVE-2025-21707 is a critical memory corruption vulnerability in Linux kernel, published on 27 Feb 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2025-21707 in the wild and no public exploit code.\n\nAffected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2025-21707/ (Markdown: https://insights.sbomify.com/CVE-2025-21707/index.md)","id":"CVE-2025-21707","markdown":"https://insights.sbomify.com/CVE-2025-21707/index.md","name":"CVE-2025-21707","record":{"aliases":["AZL-57978","BELL-CVE-2025-21707","DEBIAN-CVE-2025-21707","GHSA-mcqw-w66r-84mp","ROOT-OS-UBUNTU-2404-CVE-2025-21707","UBUNTU-CVE-2025-21707"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Linux kernel","requires_auth":"none","summary":"A use of uninitialized memory in the Linux kernel MPTCP subsystem can lead to a kernel crash, requiring a patch to fix.","user_interaction":"not_required","vuln_class":"memory_corruption"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":9.8,"severity":"critical","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-908","name":"Use of Uninitialized Resource"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: consolidate suboption status\n\nMPTCP maintains the received sub-options status is the bitmask carrying\nthe received suboptions and in several bitfields carrying per suboption\nadditional info.\n\nZeroing the bitmask before parsing is not enough to ensure a consistent\nstatus, and the MPTCP code has to additionally clear some bitfiled\ndepending on the actually parsed suboption.\n\nThe above schema is fragile, and syzbot managed to trigger a path where\na relevant bitfield is not cleared/initialized:\n\n  BUG: KMSAN: uninit-value in __mptcp_expand_seq net/mptcp/options.c:1030 [inline]\n  BUG: KMSAN: uninit-value in mptcp_expand_seq net/mptcp/protocol.h:864 [inline]\n  BUG: KMSAN: uninit-value in ack_update_msk net/mptcp/options.c:1060 [inline]\n  BUG: KMSAN: uninit-value in mptcp_incoming_options+0x2036/0x3d30 net/mptcp/options.c:1209\n   __mptcp_expand_seq net/mptcp/options.c:1030 [inline]\n   mptcp_expand_seq net/mptcp/protocol.h:864 [inline]\n   ack_update_msk net/mptcp/options.c:1060 [inline]\n   mptcp_incoming_options+0x2036/0x3d30 net/mptcp/options.c:1209\n   tcp_data_queue+0xb4/0x7be0 net/ipv4/tcp_input.c:5233\n   tcp_rcv_established+0x1061/0x2510 net/ipv4/tcp_input.c:6264\n   tcp_v4_do_rcv+0x7f3/0x11a0 net/ipv4/tcp_ipv4.c:1916\n   tcp_v4_rcv+0x51df/0x5750 net/ipv4/tcp_ipv4.c:2351\n   ip_protocol_deliver_rcu+0x2a3/0x13d0 net/ipv4/ip_input.c:205\n   ip_local_deliver_finish+0x336/0x500 net/ipv4/ip_input.c:233\n   NF_HOOK include/linux/netfilter.h:314 [inline]\n   ip_local_deliver+0x21f/0x490 net/ipv4/ip_input.c:254\n   dst_input include/net/dst.h:460 [inline]\n   ip_rcv_finish+0x4a2/0x520 net/ipv4/ip_input.c:447\n   NF_HOOK include/linux/netfilter.h:314 [inline]\n   ip_rcv+0xcd/0x380 net/ipv4/ip_input.c:567\n   __netif_receive_skb_one_core net/core/dev.c:5704 [inline]\n   __netif_receive_skb+0x319/0xa00 net/core/dev.c:5817\n   process_backlog+0x4ad/0xa50 net/core/dev.c:6149\n   __napi_poll+0xe7/0x980 net/core/dev.c:6902\n   napi_poll net/core/dev.c:6971 [inline]\n   net_rx_action+0xa5a/0x19b0 net/core/dev.c:7093\n   handle_softirqs+0x1a0/0x7c0 kernel/softirq.c:561\n   __do_softirq+0x14/0x1a kernel/softirq.c:595\n   do_softirq+0x9a/0x100 kernel/softirq.c:462\n   __local_bh_enable_ip+0x9f/0xb0 kernel/softirq.c:389\n   local_bh_enable include/linux/bottom_half.h:33 [inline]\n   rcu_read_unlock_bh include/linux/rcupdate.h:919 [inline]\n   __dev_queue_xmit+0x2758/0x57d0 net/core/dev.c:4493\n   dev_queue_xmit include/linux/netdevice.h:3168 [inline]\n   neigh_hh_output include/net/neighbour.h:523 [inline]\n   neigh_output include/net/neighbour.h:537 [inline]\n   ip_finish_output2+0x187c/0x1b70 net/ipv4/ip_output.c:236\n   __ip_finish_output+0x287/0x810\n   ip_finish_output+0x4b/0x600 net/ipv4/ip_output.c:324\n   NF_HOOK_COND include/linux/netfilter.h:303 [inline]\n   ip_output+0x15f/0x3f0 net/ipv4/ip_output.c:434\n   dst_output include/net/dst.h:450 [inline]\n   ip_local_out net/ipv4/ip_output.c:130 [inline]\n   __ip_queue_xmit+0x1f2a/0x20d0 net/ipv4/ip_output.c:536\n   ip_queue_xmit+0x60/0x80 net/ipv4/ip_output.c:550\n   __tcp_transmit_skb+0x3cea/0x4900 net/ipv4/tcp_output.c:1468\n   tcp_transmit_skb net/ipv4/tcp_output.c:1486 [inline]\n   tcp_write_xmit+0x3b90/0x9070 net/ipv4/tcp_output.c:2829\n   __tcp_push_pending_frames+0xc4/0x380 net/ipv4/tcp_output.c:3012\n   tcp_send_fin+0x9f6/0xf50 net/ipv4/tcp_output.c:3618\n   __tcp_close+0x140c/0x1550 net/ipv4/tcp.c:3130\n   __mptcp_close_ssk+0x74e/0x16f0 net/mptcp/protocol.c:2496\n   mptcp_close_ssk+0x26b/0x2c0 net/mptcp/protocol.c:2550\n   mptcp_pm_nl_rm_addr_or_subflow+0x635/0xd10 net/mptcp/pm_netlink.c:889\n   mptcp_pm_nl_rm_subflow_received net/mptcp/pm_netlink.c:924 [inline]\n   mptcp_pm_flush_addrs_and_subflows net/mptcp/pm_netlink.c:1688 [inline]\n   mptcp_nl_flush_addrs_list net/mptcp/pm_netlink.c:1709 [inline]\n   mptcp_pm_nl_flush_addrs_doit+0xe10/0x1630 net/mptcp/pm_netlink.c:1750\n   genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline]\n \n---truncated---","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"mptcp: consolidate suboption status","id":"CVE-2025-21707","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"memory_corruption","year":"2025"},"n_packages":0,"n_references":6,"next":{"headline":"net: usb: rtl8150: enable basic endpoint checking","id":"CVE-2025-21708"},"packages":[],"prev":{"headline":"mptcp: pm: only set fullmesh for subflow endp","id":"CVE-2025-21706"},"products":["Linux"],"published":"2025-02-27","related":[{"cvss_score":8.8,"headline":"Linux Kernel Out-of-Bounds Write","id":"CVE-2026-53266","kev_date_added":"2026-09-18","published":"2026-06-25"},{"cvss_score":8.8,"headline":"Linux Kernel Improper Input Validation","id":"CVE-2013-6282","kev_date_added":"2022-09-15","published":"2013-11-19"},{"cvss_score":8.4,"headline":"Linux Kernel Heap-Based Buffer Overflow","id":"CVE-2022-0185","kev_date_added":"2024-08-21","published":"2022-02-11"},{"cvss_score":8.4,"headline":"Linux Kernel Privilege Escalation","id":"CVE-2013-2094","kev_date_added":"2022-09-15","published":"2013-05-14"},{"cvss_score":7.8,"headline":"Linux Kernel Unspecified","id":"CVE-2026-53362","kev_date_added":"2026-08-27","published":"2026-07-04"},{"cvss_score":7.8,"headline":"Linux Kernel Missing Initialization of a Variable","id":"CVE-2026-46300","kev_date_added":"2026-10-28","published":"2026-05-23"},{"cvss_score":7.8,"headline":"Linux Kernel Race Condition","id":"CVE-2025-39964","kev_date_added":"2026-09-18","published":"2025-10-13"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-15","vendors":["Linux"]},"summary":"A use of uninitialized memory in the Linux kernel MPTCP subsystem can lead to a kernel crash, requiring a patch to fix.","url":"https://insights.sbomify.com/CVE-2025-21707/"}