{"id":"CVE-2024-56647","state":"PUBLISHED","title":"net: Fix icmp host relookup triggering ip_rt_bug","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: Fix icmp host relookup triggering ip_rt_bug\n\narp link failure may trigger ip_rt_bug while xfrm enabled, call trace is:\n\nWARNING: CPU: 0 PID: 0 at net/ipv4/route.c:1241 ip_rt_bug+0x14/0x20\nModules linked in:\nCPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.0-rc6-00077-g2e1b3cc9d7f7\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996),\nBIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014\nRIP: 0010:ip_rt_bug+0x14/0x20\nCall Trace:\n <IRQ>\n ip_send_skb+0x14/0x40\n __icmp_send+0x42d/0x6a0\n ipv4_link_failure+0xe2/0x1d0\n arp_error_report+0x3c/0x50\n neigh_invalidate+0x8d/0x100\n neigh_timer_handler+0x2e1/0x330\n call_timer_fn+0x21/0x120\n __run_timer_base.part.0+0x1c9/0x270\n run_timer_softirq+0x4c/0x80\n handle_softirqs+0xac/0x280\n irq_exit_rcu+0x62/0x80\n sysvec_apic_timer_interrupt+0x77/0x90\n\nThe script below reproduces this scenario:\nip xfrm policy add src 0.0.0.0/0 dst 0.0.0.0/0 \\\n\tdir out priority 0 ptype main flag localok icmp\nip l a veth1 type veth\nip a a 192.168.141.111/24 dev veth0\nip l s veth0 up\nping 192.168.141.155 -c 1\n\nicmp_route_lookup() create input routes for locally generated packets\nwhile xfrm relookup ICMP traffic.Then it will set input route\n(dst->out = ip_rt_bug) to skb for DESTUNREACH.\n\nFor ICMP err triggered by locally generated packets, dst->dev of output\nroute is loopback. Generally, xfrm relookup verification is not required\non loopback interfaces (net.ipv4.conf.lo.disable_xfrm = 1).\n\nSkip icmp relookup for locally generated packets to fix it.","publishedAt":"2024-12-27T15:02:47.969Z","updatedAt":"2026-10-15T00:59:58.769Z","severity":{"score":5.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"CISA-ADP"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"8b7817f3a959ed99d7443afc12f78a7e1fcc2063","status":"affected","lessThan":"d50981aaaefc3b04490fbc8274d37881a2b1b112","versionType":"git"},{"version":"8b7817f3a959ed99d7443afc12f78a7e1fcc2063","status":"affected","lessThan":"da54b3039d436227deebbc202cefea63bd318a38","versionType":"git"},{"version":"8b7817f3a959ed99d7443afc12f78a7e1fcc2063","status":"affected","lessThan":"9545011e7b2a8fc0cbd6e387a09f12cd41d7d82f","versionType":"git"},{"version":"8b7817f3a959ed99d7443afc12f78a7e1fcc2063","status":"affected","lessThan":"c44daa7e3c73229f7ac74985acb8c7fb909c4e0a","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv4/icmp.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.25","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.25","versionType":"semver"},{"version":"6.1.175","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.140","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.5","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.13","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv4/icmp.c"]}],"references":["https://git.kernel.org/stable/c/d50981aaaefc3b04490fbc8274d37881a2b1b112","https://git.kernel.org/stable/c/da54b3039d436227deebbc202cefea63bd318a38","https://git.kernel.org/stable/c/9545011e7b2a8fc0cbd6e387a09f12cd41d7d82f","https://git.kernel.org/stable/c/c44daa7e3c73229f7ac74985acb8c7fb909c4e0a","https://cert-portal.siemens.com/productcert/html/ssa-784472.html"],"weaknesses":[],"ingestedAt":"2026-10-29T20:08:12.933Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2024/56xxx/CVE-2024-56647.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2024-56647","state":"PUBLISHED","datePublished":"2024-12-27T15:02:47.969Z","dateUpdated":"2026-10-15T00:59:58.769Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2024-12-27T15:00:39.840Z"},"containers":{"cna":{"title":"net: Fix icmp host relookup triggering ip_rt_bug","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: Fix icmp host relookup triggering ip_rt_bug\n\narp link failure may trigger ip_rt_bug while xfrm enabled, call trace is:\n\nWARNING: CPU: 0 PID: 0 at net/ipv4/route.c:1241 ip_rt_bug+0x14/0x20\nModules linked in:\nCPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.0-rc6-00077-g2e1b3cc9d7f7\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996),\nBIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014\nRIP: 0010:ip_rt_bug+0x14/0x20\nCall Trace:\n <IRQ>\n ip_send_skb+0x14/0x40\n __icmp_send+0x42d/0x6a0\n ipv4_link_failure+0xe2/0x1d0\n arp_error_report+0x3c/0x50\n neigh_invalidate+0x8d/0x100\n neigh_timer_handler+0x2e1/0x330\n call_timer_fn+0x21/0x120\n __run_timer_base.part.0+0x1c9/0x270\n run_timer_softirq+0x4c/0x80\n handle_softirqs+0xac/0x280\n irq_exit_rcu+0x62/0x80\n sysvec_apic_timer_interrupt+0x77/0x90\n\nThe script below reproduces this scenario:\nip xfrm policy add src 0.0.0.0/0 dst 0.0.0.0/0 \\\n\tdir out priority 0 ptype main flag localok icmp\nip l a veth1 type veth\nip a a 192.168.141.111/24 dev veth0\nip l s veth0 up\nping 192.168.141.155 -c 1\n\nicmp_route_lookup() create input routes for locally generated packets\nwhile xfrm relookup ICMP traffic.Then it will set input route\n(dst->out = ip_rt_bug) to skb for DESTUNREACH.\n\nFor ICMP err triggered by locally generated packets, dst->dev of output\nroute is loopback. Generally, xfrm relookup verification is not required\non loopback interfaces (net.ipv4.conf.lo.disable_xfrm = 1).\n\nSkip icmp relookup for locally generated packets to fix it."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"8b7817f3a959ed99d7443afc12f78a7e1fcc2063","status":"affected","lessThan":"d50981aaaefc3b04490fbc8274d37881a2b1b112","versionType":"git"},{"version":"8b7817f3a959ed99d7443afc12f78a7e1fcc2063","status":"affected","lessThan":"da54b3039d436227deebbc202cefea63bd318a38","versionType":"git"},{"version":"8b7817f3a959ed99d7443afc12f78a7e1fcc2063","status":"affected","lessThan":"9545011e7b2a8fc0cbd6e387a09f12cd41d7d82f","versionType":"git"},{"version":"8b7817f3a959ed99d7443afc12f78a7e1fcc2063","status":"affected","lessThan":"c44daa7e3c73229f7ac74985acb8c7fb909c4e0a","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv4/icmp.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.25","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.25","versionType":"semver"},{"version":"6.1.175","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.140","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.5","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.13","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv4/icmp.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/d50981aaaefc3b04490fbc8274d37881a2b1b112"},{"url":"https://git.kernel.org/stable/c/da54b3039d436227deebbc202cefea63bd318a38"},{"url":"https://git.kernel.org/stable/c/9545011e7b2a8fc0cbd6e387a09f12cd41d7d82f"},{"url":"https://git.kernel.org/stable/c/c44daa7e3c73229f7ac74985acb8c7fb909c4e0a"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-06-01T16:04:51.318Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"6.1.175"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"6.6.140"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"6.12.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.25","versionEndExcluding":"6.13"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":5.5,"attackVector":"LOCAL","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"id":"CVE-2024-56647","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2025-10-01T20:00:32.629636Z"}}}],"problemTypes":[{"descriptions":[{"lang":"en","type":"CWE","description":"CWE-noinfo Not enough information"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-10-01T20:07:11.763Z"}},{"affected":[{"vendor":"Siemens","product":"SIMATIC S7-1500 TM MFP - GNU/Linux subsystem","defaultStatus":"unknown","versions":[{"version":"0","status":"affected","lessThan":"*","versionType":"custom"}]}],"references":[{"url":"https://cert-portal.siemens.com/productcert/html/ssa-784472.html"}],"providerMetadata":{"shortName":"siemens-SADP","orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","dateUpdated":"2026-10-15T00:59:58.769Z"},"x_adpType":"supplier"}]}}}