{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-47126 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2021-47126 is a high-severity memory corruption vulnerability in Linux kernel, published on 15 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-2021-47126 and fix it if it is affected.\n\nWhat it is: CVE-2021-47126 is a high-severity memory corruption vulnerability in Linux kernel, published on 15 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-2021-47126 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-2021-47126/ (Markdown: https://insights.sbomify.com/CVE-2021-47126/index.md)","id":"CVE-2021-47126","markdown":"https://insights.sbomify.com/CVE-2021-47126/index.md","name":"CVE-2021-47126","record":{"aliases":["DEBIAN-CVE-2021-47126","GHSA-q96w-v39p-hcjw","UBUNTU-CVE-2021-47126"],"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 slab-out-of-bounds read in the Linux kernel IPv6 routing code can cause a system crash, requiring a kernel patch.","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":7.8,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-125","name":"Out-of-bounds Read"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: Fix KASAN: slab-out-of-bounds Read in fib6_nh_flush_exceptions\n\nReported by syzbot:\nHEAD commit:    90c911ad Merge tag 'fixes' of git://git.kernel.org/pub/scm..\ngit tree:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master\ndashboard link: https://syzkaller.appspot.com/bug?extid=123aa35098fd3c000eb7\ncompiler:       Debian clang version 11.0.1-2\n\n==================================================================\nBUG: KASAN: slab-out-of-bounds in fib6_nh_get_excptn_bucket net/ipv6/route.c:1604 [inline]\nBUG: KASAN: slab-out-of-bounds in fib6_nh_flush_exceptions+0xbd/0x360 net/ipv6/route.c:1732\nRead of size 8 at addr ffff8880145c78f8 by task syz-executor.4/17760\n\nCPU: 0 PID: 17760 Comm: syz-executor.4 Not tainted 5.12.0-rc8-syzkaller #0\nCall Trace:\n \u003cIRQ\u003e\n __dump_stack lib/dump_stack.c:79 [inline]\n dump_stack+0x202/0x31e lib/dump_stack.c:120\n print_address_description+0x5f/0x3b0 mm/kasan/report.c:232\n __kasan_report mm/kasan/report.c:399 [inline]\n kasan_report+0x15c/0x200 mm/kasan/report.c:416\n fib6_nh_get_excptn_bucket net/ipv6/route.c:1604 [inline]\n fib6_nh_flush_exceptions+0xbd/0x360 net/ipv6/route.c:1732\n fib6_nh_release+0x9a/0x430 net/ipv6/route.c:3536\n fib6_info_destroy_rcu+0xcb/0x1c0 net/ipv6/ip6_fib.c:174\n rcu_do_batch kernel/rcu/tree.c:2559 [inline]\n rcu_core+0x8f6/0x1450 kernel/rcu/tree.c:2794\n __do_softirq+0x372/0x7a6 kernel/softirq.c:345\n invoke_softirq kernel/softirq.c:221 [inline]\n __irq_exit_rcu+0x22c/0x260 kernel/softirq.c:422\n irq_exit_rcu+0x5/0x20 kernel/softirq.c:434\n sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1100\n \u003c/IRQ\u003e\n asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:632\nRIP: 0010:lock_acquire+0x1f6/0x720 kernel/locking/lockdep.c:5515\nCode: f6 84 24 a1 00 00 00 02 0f 85 8d 02 00 00 f7 c3 00 02 00 00 49 bd 00 00 00 00 00 fc ff df 74 01 fb 48 c7 44 24 40 0e 36 e0 45 \u003c4b\u003e c7 44 3d 00 00 00 00 00 4b c7 44 3d 09 00 00 00 00 43 c7 44 3d\nRSP: 0018:ffffc90009e06560 EFLAGS: 00000206\nRAX: 1ffff920013c0cc0 RBX: 0000000000000246 RCX: dffffc0000000000\nRDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000\nRBP: ffffc90009e066e0 R08: dffffc0000000000 R09: fffffbfff1f992b1\nR10: fffffbfff1f992b1 R11: 0000000000000000 R12: 0000000000000000\nR13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff920013c0cb4\n rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:267\n rcu_read_lock include/linux/rcupdate.h:656 [inline]\n ext4_get_group_info+0xea/0x340 fs/ext4/ext4.h:3231\n ext4_mb_prefetch+0x123/0x5d0 fs/ext4/mballoc.c:2212\n ext4_mb_regular_allocator+0x8a5/0x28f0 fs/ext4/mballoc.c:2379\n ext4_mb_new_blocks+0xc6e/0x24f0 fs/ext4/mballoc.c:4982\n ext4_ext_map_blocks+0x2be3/0x7210 fs/ext4/extents.c:4238\n ext4_map_blocks+0xab3/0x1cb0 fs/ext4/inode.c:638\n ext4_getblk+0x187/0x6c0 fs/ext4/inode.c:848\n ext4_bread+0x2a/0x1c0 fs/ext4/inode.c:900\n ext4_append+0x1a4/0x360 fs/ext4/namei.c:67\n ext4_init_new_dir+0x337/0xa10 fs/ext4/namei.c:2768\n ext4_mkdir+0x4b8/0xc00 fs/ext4/namei.c:2814\n vfs_mkdir+0x45b/0x640 fs/namei.c:3819\n ovl_do_mkdir fs/overlayfs/overlayfs.h:161 [inline]\n ovl_mkdir_real+0x53/0x1a0 fs/overlayfs/dir.c:146\n ovl_create_real+0x280/0x490 fs/overlayfs/dir.c:193\n ovl_workdir_create+0x425/0x600 fs/overlayfs/super.c:788\n ovl_make_workdir+0xed/0x1140 fs/overlayfs/super.c:1355\n ovl_get_workdir fs/overlayfs/super.c:1492 [inline]\n ovl_fill_super+0x39ee/0x5370 fs/overlayfs/super.c:2035\n mount_nodev+0x52/0xe0 fs/super.c:1413\n legacy_get_tree+0xea/0x180 fs/fs_context.c:592\n vfs_get_tree+0x86/0x270 fs/super.c:1497\n do_new_mount fs/namespace.c:2903 [inline]\n path_mount+0x196f/0x2be0 fs/namespace.c:3233\n do_mount fs/namespace.c:3246 [inline]\n __do_sys_mount fs/namespace.c:3454 [inline]\n __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3431\n do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46\n entry_SYSCALL_64_after_hwframe+0x44/0xae\nRIP: 0033:0x4665f9\nCode: ff ff c3 66 2e 0f 1f 84 \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":"ipv6: Fix KASAN: slab-out-of-bounds Read in fib6_nh_flush_exceptions","id":"CVE-2021-47126","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"memory_corruption","year":"2021"},"n_packages":0,"n_references":4,"next":{"headline":"ice: track AF_XDP ZC enabled queues in bitmap","id":"CVE-2021-47127"},"packages":[],"prev":{"headline":"sch_htb: fix refcount leak in htb_parent_to_leaf_offload","id":"CVE-2021-47125"},"products":["Linux"],"published":"2024-03-15","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":"2026-08-05","vendors":["Linux"]},"summary":"A slab-out-of-bounds read in the Linux kernel IPv6 routing code can cause a system crash, requiring a kernel patch.","url":"https://insights.sbomify.com/CVE-2021-47126/"}