{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2023-53343 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2023-53343 is a medium-severity vulnerability in Linux kernel, published on 17 Sep 2025. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2023-53343 and fix it if it is affected.\n\nWhat it is: CVE-2023-53343 is a medium-severity vulnerability in Linux kernel, published on 17 Sep 2025. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2023-53343 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-2023-53343/ (Markdown: https://insights.sbomify.com/CVE-2023-53343/index.md)","id":"CVE-2023-53343","markdown":"https://insights.sbomify.com/CVE-2023-53343/index.md","name":"CVE-2023-53343","record":{"aliases":["BELL-CVE-2023-53343","DEBIAN-CVE-2023-53343","GHSA-wcr6-fh62-j9wm","UBUNTU-CVE-2023-53343"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A local attacker can cause a kernel crash by sending crafted IPv6 packets with specific extension headers, leading to a denial of service.","user_interaction":"not_required","vuln_class":"null_dereference"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":5.5,"severity":"medium","source":"cisa-adp","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-476","name":"NULL Pointer Dereference"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nicmp6: Fix null-ptr-deref of ip6_null_entry-\u003ert6i_idev in icmp6_dev().\n\nWith some IPv6 Ext Hdr (RPL, SRv6, etc.), we can send a packet that\nhas the link-local address as src and dst IP and will be forwarded to\nan external IP in the IPv6 Ext Hdr.\n\nFor example, the script below generates a packet whose src IP is the\nlink-local address and dst is updated to 11::.\n\n  # for f in $(find /proc/sys/net/ -name *seg6_enabled*); do echo 1 \u003e $f; done\n  # python3\n  \u003e\u003e\u003e from socket import *\n  \u003e\u003e\u003e from scapy.all import *\n  \u003e\u003e\u003e\n  \u003e\u003e\u003e SRC_ADDR = DST_ADDR = \"fe80::5054:ff:fe12:3456\"\n  \u003e\u003e\u003e\n  \u003e\u003e\u003e pkt = IPv6(src=SRC_ADDR, dst=DST_ADDR)\n  \u003e\u003e\u003e pkt /= IPv6ExtHdrSegmentRouting(type=4, addresses=[\"11::\", \"22::\"], segleft=1)\n  \u003e\u003e\u003e\n  \u003e\u003e\u003e sk = socket(AF_INET6, SOCK_RAW, IPPROTO_RAW)\n  \u003e\u003e\u003e sk.sendto(bytes(pkt), (DST_ADDR, 0))\n\nFor such a packet, we call ip6_route_input() to look up a route for the\nnext destination in these three functions depending on the header type.\n\n  * ipv6_rthdr_rcv()\n  * ipv6_rpl_srh_rcv()\n  * ipv6_srh_rcv()\n\nIf no route is found, ip6_null_entry is set to skb, and the following\ndst_input(skb) calls ip6_pkt_drop().\n\nFinally, in icmp6_dev(), we dereference skb_rt6_info(skb)-\u003ert6i_idev-\u003edev\nas the input device is the loopback interface.  Then, we have to check if\nskb_rt6_info(skb)-\u003ert6i_idev is NULL or not to avoid NULL pointer deref\nfor ip6_null_entry.\n\nBUG: kernel NULL pointer dereference, address: 0000000000000000\n PF: supervisor read access in kernel mode\n PF: error_code(0x0000) - not-present page\nPGD 0 P4D 0\nOops: 0000 [#1] PREEMPT SMP PTI\nCPU: 0 PID: 157 Comm: python3 Not tainted 6.4.0-11996-gb121d614371c #35\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014\nRIP: 0010:icmp6_send (net/ipv6/icmp.c:436 net/ipv6/icmp.c:503)\nCode: fe ff ff 48 c7 40 30 c0 86 5d 83 e8 c6 44 1c 00 e9 c8 fc ff ff 49 8b 46 58 48 83 e0 fe 0f 84 4a fb ff ff 48 8b 80 d0 00 00 00 \u003c48\u003e 8b 00 44 8b 88 e0 00 00 00 e9 34 fb ff ff 4d 85 ed 0f 85 69 01\nRSP: 0018:ffffc90000003c70 EFLAGS: 00000286\nRAX: 0000000000000000 RBX: 0000000000000001 RCX: 00000000000000e0\nRDX: 0000000000000021 RSI: 0000000000000000 RDI: ffff888006d72a18\nRBP: ffffc90000003d80 R08: 0000000000000000 R09: 0000000000000001\nR10: ffffc90000003d98 R11: 0000000000000040 R12: ffff888006d72a10\nR13: 0000000000000000 R14: ffff8880057fb800 R15: ffffffff835d86c0\nFS:  00007f9dc72ee740(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 0000000000000000 CR3: 00000000057b2000 CR4: 00000000007506f0\nPKRU: 55555554\nCall Trace:\n \u003cIRQ\u003e\n ip6_pkt_drop (net/ipv6/route.c:4513)\n ipv6_rthdr_rcv (net/ipv6/exthdrs.c:640 net/ipv6/exthdrs.c:686)\n ip6_protocol_deliver_rcu (net/ipv6/ip6_input.c:437 (discriminator 5))\n ip6_input_finish (./include/linux/rcupdate.h:781 net/ipv6/ip6_input.c:483)\n __netif_receive_skb_one_core (net/core/dev.c:5455)\n process_backlog (./include/linux/rcupdate.h:781 net/core/dev.c:5895)\n __napi_poll (net/core/dev.c:6460)\n net_rx_action (net/core/dev.c:6529 net/core/dev.c:6660)\n __do_softirq (./arch/x86/include/asm/jump_label.h:27 ./include/linux/jump_label.h:207 ./include/trace/events/irq.h:142 kernel/softirq.c:554)\n do_softirq (kernel/softirq.c:454 kernel/softirq.c:441)\n \u003c/IRQ\u003e\n \u003cTASK\u003e\n __local_bh_enable_ip (kernel/softirq.c:381)\n __dev_queue_xmit (net/core/dev.c:4231)\n ip6_finish_output2 (./include/net/neighbour.h:544 net/ipv6/ip6_output.c:135)\n rawv6_sendmsg (./include/net/dst.h:458 ./include/linux/netfilter.h:303 net/ipv6/raw.c:656 net/ipv6/raw.c:914)\n sock_sendmsg (net/socket.c:725 net/socket.c:748)\n __sys_sendto (net/socket.c:2134)\n __x64_sys_sendto (net/socket.c:2146 net/socket.c:2142 net/socket.c:2142)\n do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)\n entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)\nRIP: 0033:0x7f9dc751baea\nCode: d8 64 89 02 48 c7 c0 ff f\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":"icmp6: Fix null-ptr-deref of ip6_null_entry-\u003ert6i_idev in icmp6_dev().","id":"CVE-2023-53343","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"null_dereference","year":"2023"},"n_packages":0,"n_references":7,"next":{"headline":"can: bcm: bcm_tx_setup(): fix KMSAN uninit-value in vfs_write","id":"CVE-2023-53344"},"packages":[],"prev":{"headline":"net: marvell: prestera: fix handling IPv4 routes with nhid","id":"CVE-2023-53342"},"products":["Linux"],"published":"2025-09-17","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":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-05-11","vendors":["Linux"]},"summary":"A local attacker can cause a kernel crash by sending crafted IPv6 packets with specific extension headers, leading to a denial of service.","url":"https://insights.sbomify.com/CVE-2023-53343/"}