{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2021-47588", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2021-47588", "idYear": 2021, "status": "PUBLISHED", "publishedAt": "2024-06-19T14:53:52.909Z", "updatedAt": "2026-08-05T08:48:30.684Z", "importedAt": "2026-10-24T01:56:36.661Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "sit: do not call ipip6_dev_free() from sit_init_net()", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nsit: do not call ipip6_dev_free() from sit_init_net()\n\nipip6_dev_free is sit dev->priv_destructor, already called\nby register_netdevice() if something goes wrong.\n\nAlternative would be to make ipip6_dev_free() robust against\nmultiple invocations, but other drivers do not implement this\nstrategy.\n\nsyzbot reported:\n\ndst_release underflow\nWARNING: CPU: 0 PID: 5059 at net/core/dst.c:173 dst_release+0xd8/0xe0 net/core/dst.c:173\nModules linked in:\nCPU: 1 PID: 5059 Comm: syz-executor.4 Not tainted 5.16.0-rc5-syzkaller #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011\nRIP: 0010:dst_release+0xd8/0xe0 net/core/dst.c:173\nCode: 4c 89 f2 89 d9 31 c0 5b 41 5e 5d e9 da d5 44 f9 e8 1d 90 5f f9 c6 05 87 48 c6 05 01 48 c7 c7 80 44 99 8b 31 c0 e8 e8 67 29 f9 <0f> 0b eb 85 0f 1f 40 00 53 48 89 fb e8 f7 8f 5f f9 48 83 c3 a8 48\nRSP: 0018:ffffc9000aa5faa0 EFLAGS: 00010246\nRAX: d6894a925dd15a00 RBX: 00000000ffffffff RCX: 0000000000040000\nRDX: ffffc90005e19000 RSI: 000000000003ffff RDI: 0000000000040000\nRBP: 0000000000000000 R08: ffffffff816a1f42 R09: ffffed1017344f2c\nR10: ffffed1017344f2c R11: 0000000000000000 R12: 0000607f462b1358\nR13: 1ffffffff1bfd305 R14: ffffe8ffffcb1358 R15: dffffc0000000000\nFS: 00007f66c71a2700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000\nCS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00007f88aaed5058 CR3: 0000000023e0f000 CR4: 00000000003506f0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\nCall Trace:\n \n dst_cache_destroy+0x107/0x1e0 net/core/dst_cache.c:160\n ipip6_dev_free net/ipv6/sit.c:1414 [inline]\n sit_init_net+0x229/0x550 net/ipv6/sit.c:1936\n ops_init+0x313/0x430 net/core/net_namespace.c:140\n setup_net+0x35b/0x9d0 net/core/net_namespace.c:326\n copy_net_ns+0x359/0x5c0 net/core/net_namespace.c:470\n create_new_namespaces+0x4ce/0xa00 kernel/nsproxy.c:110\n unshare_nsproxy_namespaces+0x11e/0x180 kernel/nsproxy.c:226\n ksys_unshare+0x57d/0xb50 kernel/fork.c:3075\n __do_sys_unshare kernel/fork.c:3146 [inline]\n __se_sys_unshare kernel/fork.c:3144 [inline]\n __x64_sys_unshare+0x34/0x40 kernel/fork.c:3144\n do_syscall_x64 arch/x86/entry/common.c:50 [inline]\n do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80\n entry_SYSCALL_64_after_hwframe+0x44/0xae\nRIP: 0033:0x7f66c882ce99\nCode: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48\nRSP: 002b:00007f66c71a2168 EFLAGS: 00000246 ORIG_RAX: 0000000000000110\nRAX: ffffffffffffffda RBX: 00007f66c893ff60 RCX: 00007f66c882ce99\nRDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000048040200\nRBP: 00007f66c8886ff1 R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000\nR13: 00007fff6634832f R14: 00007f66c71a2300 R15: 0000000000022000\n ", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "cf124db566e6b036b8bcbe8decbed740bdfac8c6", "status": "affected", "versionType": "git", "lessThan": "4e1797914d8f223726ff6ae5ece4f97d73f21bab" }, { "version": "cf124db566e6b036b8bcbe8decbed740bdfac8c6", "status": "affected", "versionType": "git", "lessThan": "e56b65c1e74d7f706d74b51baba15187be2fb4b5" }, { "version": "cf124db566e6b036b8bcbe8decbed740bdfac8c6", "status": "affected", "versionType": "git", "lessThan": "ad0ed314d6167b212939e3839428ba0c8bb16adb" }, { "version": "cf124db566e6b036b8bcbe8decbed740bdfac8c6", "status": "affected", "versionType": "git", "lessThan": "6f46c59e60b64620d5d386c8ee2eaa11ebe3b595" }, { "version": "cf124db566e6b036b8bcbe8decbed740bdfac8c6", "status": "affected", "versionType": "git", "lessThan": "44a6c846bc3a7efe7d394bab8b2ae3b7f580e190" }, { "version": "cf124db566e6b036b8bcbe8decbed740bdfac8c6", "status": "affected", "versionType": "git", "lessThan": "e28587cc491ef0f3c51258fdc87fbc386b1d4c59" }, { "version": "95876855a55072572895a236b156ffb357fd5538", "status": "affected", "versionType": "git" }, { "version": "4.11.9", "status": "affected", "versionType": "semver", "lessThan": "4.12" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "4.12", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "4.12" }, { "version": "4.14.259", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "4.14.*" }, { "version": "4.19.222", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "4.19.*" }, { "version": "5.4.168", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.4.*" }, { "version": "5.10.88", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.11", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "5.16", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }