{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-47146 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2021-47146 is a medium-severity denial of service vulnerability in Linux kernel, published on 25 Mar 2024. 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-2021-47146 and fix it if it is affected.\n\nWhat it is: CVE-2021-47146 is a medium-severity denial of service vulnerability in Linux kernel, published on 25 Mar 2024. 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-2021-47146 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-2021-47146/ (Markdown: https://insights.sbomify.com/CVE-2021-47146/index.md)","id":"CVE-2021-47146","markdown":"https://insights.sbomify.com/CVE-2021-47146/index.md","name":"CVE-2021-47146","record":{"aliases":["DEBIAN-CVE-2021-47146","GHSA-w7p2-j7r7-m47f","UBUNTU-CVE-2021-47146"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A kernel panic in the Linux kernel's MLD implementation allows local attackers to cause a denial of service via crafted network configurations.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":5.5,"severity":"medium","source":"nvd","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmld: fix panic in mld_newpack()\n\nmld_newpack() doesn't allow to allocate high order page,\nonly order-0 allocation is allowed.\nIf headroom size is too large, a kernel panic could occur in skb_put().\n\nTest commands:\n    ip netns del A\n    ip netns del B\n    ip netns add A\n    ip netns add B\n    ip link add veth0 type veth peer name veth1\n    ip link set veth0 netns A\n    ip link set veth1 netns B\n\n    ip netns exec A ip link set lo up\n    ip netns exec A ip link set veth0 up\n    ip netns exec A ip -6 a a 2001:db8:0::1/64 dev veth0\n    ip netns exec B ip link set lo up\n    ip netns exec B ip link set veth1 up\n    ip netns exec B ip -6 a a 2001:db8:0::2/64 dev veth1\n    for i in {1..99}\n    do\n        let A=$i-1\n        ip netns exec A ip link add ip6gre$i type ip6gre \\\n\tlocal 2001:db8:$A::1 remote 2001:db8:$A::2 encaplimit 100\n        ip netns exec A ip -6 a a 2001:db8:$i::1/64 dev ip6gre$i\n        ip netns exec A ip link set ip6gre$i up\n\n        ip netns exec B ip link add ip6gre$i type ip6gre \\\n\tlocal 2001:db8:$A::2 remote 2001:db8:$A::1 encaplimit 100\n        ip netns exec B ip -6 a a 2001:db8:$i::2/64 dev ip6gre$i\n        ip netns exec B ip link set ip6gre$i up\n    done\n\nSplat looks like:\nkernel BUG at net/core/skbuff.c:110!\ninvalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI\nCPU: 0 PID: 7 Comm: kworker/0:1 Not tainted 5.12.0+ #891\nWorkqueue: ipv6_addrconf addrconf_dad_work\nRIP: 0010:skb_panic+0x15d/0x15f\nCode: 92 fe 4c 8b 4c 24 10 53 8b 4d 70 45 89 e0 48 c7 c7 00 ae 79 83\n41 57 41 56 41 55 48 8b 54 24 a6 26 f9 ff \u003c0f\u003e 0b 48 8b 6c 24 20 89\n34 24 e8 4a 4e 92 fe 8b 34 24 48 c7 c1 20\nRSP: 0018:ffff88810091f820 EFLAGS: 00010282\nRAX: 0000000000000089 RBX: ffff8881086e9000 RCX: 0000000000000000\nRDX: 0000000000000089 RSI: 0000000000000008 RDI: ffffed1020123efb\nRBP: ffff888005f6eac0 R08: ffffed1022fc0031 R09: ffffed1022fc0031\nR10: ffff888117e00187 R11: ffffed1022fc0030 R12: 0000000000000028\nR13: ffff888008284eb0 R14: 0000000000000ed8 R15: 0000000000000ec0\nFS:  0000000000000000(0000) GS:ffff888117c00000(0000)\nknlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00007f8b801c5640 CR3: 0000000033c2c006 CR4: 00000000003706f0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\nCall Trace:\n ? ip6_mc_hdr.isra.26.constprop.46+0x12a/0x600\n ? ip6_mc_hdr.isra.26.constprop.46+0x12a/0x600\n skb_put.cold.104+0x22/0x22\n ip6_mc_hdr.isra.26.constprop.46+0x12a/0x600\n ? rcu_read_lock_sched_held+0x91/0xc0\n mld_newpack+0x398/0x8f0\n ? ip6_mc_hdr.isra.26.constprop.46+0x600/0x600\n ? lock_contended+0xc40/0xc40\n add_grhead.isra.33+0x280/0x380\n add_grec+0x5ca/0xff0\n ? mld_sendpack+0xf40/0xf40\n ? lock_downgrade+0x690/0x690\n mld_send_initial_cr.part.34+0xb9/0x180\n ipv6_mc_dad_complete+0x15d/0x1b0\n addrconf_dad_completed+0x8d2/0xbb0\n ? lock_downgrade+0x690/0x690\n ? addrconf_rs_timer+0x660/0x660\n ? addrconf_dad_work+0x73c/0x10e0\n addrconf_dad_work+0x73c/0x10e0\n\nAllowing high order page allocation could fix this problem.","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":"mld: fix panic in mld_newpack()","id":"CVE-2021-47146","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"denial_of_service","year":"2021"},"n_packages":0,"n_references":8,"next":{"headline":"ptp: ocp: Fix a resource leak in an error handling path","id":"CVE-2021-47147"},"packages":[],"prev":{"headline":"btrfs: do not BUG_ON in link_to_fixup_dir","id":"CVE-2021-47145"},"products":["Linux"],"published":"2024-03-25","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":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-05-11","vendors":["Linux"]},"summary":"A kernel panic in the Linux kernel's MLD implementation allows local attackers to cause a denial of service via crafted network configurations.","url":"https://insights.sbomify.com/CVE-2021-47146/"}