{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-47595 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2021-47595 is a medium-severity vulnerability in Linux kernel, published on 19 Jun 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-2021-47595 and fix it if it is affected.\n\nWhat it is: CVE-2021-47595 is a medium-severity vulnerability in Linux kernel, published on 19 Jun 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-2021-47595 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-2021-47595/ (Markdown: https://insights.sbomify.com/CVE-2021-47595/index.md)","id":"CVE-2021-47595","markdown":"https://insights.sbomify.com/CVE-2021-47595/index.md","name":"CVE-2021-47595","record":{"aliases":["DEBIAN-CVE-2021-47595","GHSA-7jvp-hvfw-w5mc","UBUNTU-CVE-2021-47595"],"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 flaw in the Linux kernel's ETS scheduler allows a local attacker to cause a system crash by manipulating traffic control classes.","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":"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\nnet/sched: sch_ets: don't remove idle classes from the round-robin list\n\nShuang reported that the following script:\n\n 1) tc qdisc add dev ddd0 handle 10: parent 1: ets bands 8 strict 4 priomap 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7\n 2) mausezahn ddd0  -A 10.10.10.1 -B 10.10.10.2 -c 0 -a own -b 00:c1:a0:c1:a0:00 -t udp \u0026\n 3) tc qdisc change dev ddd0 handle 10: ets bands 4 strict 2 quanta 2500 2500 priomap 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3\n\ncrashes systematically when line 2) is commented:\n\n list_del corruption, ffff8e028404bd30-\u003enext is LIST_POISON1 (dead000000000100)\n ------------[ cut here ]------------\n kernel BUG at lib/list_debug.c:47!\n invalid opcode: 0000 [#1] PREEMPT SMP NOPTI\n CPU: 0 PID: 954 Comm: tc Not tainted 5.16.0-rc4+ #478\n Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014\n RIP: 0010:__list_del_entry_valid.cold.1+0x12/0x47\n Code: fe ff 0f 0b 48 89 c1 4c 89 c6 48 c7 c7 08 42 1b 87 e8 1d c5 fe ff 0f 0b 48 89 fe 48 89 c2 48 c7 c7 98 42 1b 87 e8 09 c5 fe ff \u003c0f\u003e 0b 48 c7 c7 48 43 1b 87 e8 fb c4 fe ff 0f 0b 48 89 f2 48 89 fe\n RSP: 0018:ffffae46807a3888 EFLAGS: 00010246\n RAX: 000000000000004e RBX: 0000000000000007 RCX: 0000000000000202\n RDX: 0000000000000000 RSI: ffffffff871ac536 RDI: 00000000ffffffff\n RBP: ffffae46807a3a10 R08: 0000000000000000 R09: c0000000ffff7fff\n R10: 0000000000000001 R11: ffffae46807a36a8 R12: ffff8e028404b800\n R13: ffff8e028404bd30 R14: dead000000000100 R15: ffff8e02fafa2400\n FS:  00007efdc92e4480(0000) GS:ffff8e02fb600000(0000) knlGS:0000000000000000\n CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 0000000000682f48 CR3: 00000001058be000 CR4: 0000000000350ef0\n Call Trace:\n  \u003cTASK\u003e\n  ets_qdisc_change+0x58b/0xa70 [sch_ets]\n  tc_modify_qdisc+0x323/0x880\n  rtnetlink_rcv_msg+0x169/0x4a0\n  netlink_rcv_skb+0x50/0x100\n  netlink_unicast+0x1a5/0x280\n  netlink_sendmsg+0x257/0x4d0\n  sock_sendmsg+0x5b/0x60\n  ____sys_sendmsg+0x1f2/0x260\n  ___sys_sendmsg+0x7c/0xc0\n  __sys_sendmsg+0x57/0xa0\n  do_syscall_64+0x3a/0x80\n  entry_SYSCALL_64_after_hwframe+0x44/0xae\n RIP: 0033:0x7efdc8031338\n Code: 89 02 48 c7 c0 ff ff ff ff eb b5 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 8d 05 25 43 2c 00 8b 00 85 c0 75 17 b8 2e 00 00 00 0f 05 \u003c48\u003e 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 41 54 41 89 d4 55\n RSP: 002b:00007ffdf1ce9828 EFLAGS: 00000246 ORIG_RAX: 000000000000002e\n RAX: ffffffffffffffda RBX: 0000000061b37a97 RCX: 00007efdc8031338\n RDX: 0000000000000000 RSI: 00007ffdf1ce9890 RDI: 0000000000000003\n RBP: 0000000000000000 R08: 0000000000000001 R09: 000000000078a940\n R10: 000000000000000c R11: 0000000000000246 R12: 0000000000000001\n R13: 0000000000688880 R14: 0000000000000000 R15: 0000000000000000\n  \u003c/TASK\u003e\n Modules linked in: sch_ets sch_tbf dummy rfkill iTCO_wdt iTCO_vendor_support intel_rapl_msr intel_rapl_common joydev pcspkr i2c_i801 virtio_balloon i2c_smbus lpc_ich ip_tables xfs libcrc32c crct10dif_pclmul crc32_pclmul crc32c_intel serio_raw ghash_clmulni_intel ahci libahci libata virtio_blk virtio_console virtio_net net_failover failover sunrpc dm_mirror dm_region_hash dm_log dm_mod [last unloaded: sch_ets]\n ---[ end trace f35878d1912655c2 ]---\n RIP: 0010:__list_del_entry_valid.cold.1+0x12/0x47\n Code: fe ff 0f 0b 48 89 c1 4c 89 c6 48 c7 c7 08 42 1b 87 e8 1d c5 fe ff 0f 0b 48 89 fe 48 89 c2 48 c7 c7 98 42 1b 87 e8 09 c5 fe ff \u003c0f\u003e 0b 48 c7 c7 48 43 1b 87 e8 fb c4 fe ff 0f 0b 48 89 f2 48 89 fe\n RSP: 0018:ffffae46807a3888 EFLAGS: 00010246\n RAX: 000000000000004e RBX: 0000000000000007 RCX: 0000000000000202\n RDX: 0000000000000000 RSI: ffffffff871ac536 RDI: 00000000ffffffff\n RBP: ffffae46807a3a10 R08: 0000000000000000 R09: c0000000ffff7fff\n R10: 0000000000000001 R11: ffffae46807a36a8 R12: ffff8e028404b800\n R13: ffff8e028404bd30 R14: dead000000000100 R15: ffff8e02fafa2400\n FS:  00007efdc92e4480(0000) GS:ffff8e02fb600000(0000) knlGS:0000000000000000\n CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n CR2: 000000000\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":"net/sched: sch_ets: don't remove idle classes from the round-robin list","id":"CVE-2021-47595","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"null_dereference","year":"2021"},"n_packages":0,"n_references":3,"next":{"headline":"net: hns3: fix use-after-free bug in hclgevf_send_mbx_msg","id":"CVE-2021-47596"},"packages":[],"prev":{"headline":"mptcp: never allow the PM to close a listener subflow","id":"CVE-2021-47594"},"products":["Linux"],"published":"2024-06-19","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 flaw in the Linux kernel's ETS scheduler allows a local attacker to cause a system crash by manipulating traffic control classes.","url":"https://insights.sbomify.com/CVE-2021-47595/"}