{"id":"CVE-2025-38732","state":"PUBLISHED","title":"netfilter: nf_reject: don't leak dst refcount for loopback packets","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_reject: don't leak dst refcount for loopback packets\n\nrecent patches to add a WARN() when replacing skb dst entry found an\nold bug:\n\nWARNING: include/linux/skbuff.h:1165 skb_dst_check_unset include/linux/skbuff.h:1164 [inline]\nWARNING: include/linux/skbuff.h:1165 skb_dst_set include/linux/skbuff.h:1210 [inline]\nWARNING: include/linux/skbuff.h:1165 nf_reject_fill_skb_dst+0x2a4/0x330 net/ipv4/netfilter/nf_reject_ipv4.c:234\n[..]\nCall Trace:\n nf_send_unreach+0x17b/0x6e0 net/ipv4/netfilter/nf_reject_ipv4.c:325\n nft_reject_inet_eval+0x4bc/0x690 net/netfilter/nft_reject_inet.c:27\n expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]\n ..\n\nThis is because blamed commit forgot about loopback packets.\nSuch packets already have a dst_entry attached, even at PRE_ROUTING stage.\n\nInstead of checking hook just check if the skb already has a route\nattached to it.","publishedAt":"2025-09-05T17:20:31.934Z","updatedAt":"2026-10-15T01:07:52.848Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"f53b9b0bdc59c0823679f2e3214e0d538f5951b9","status":"affected","lessThan":"7b8b503c06274ef3c6c1a107743f1ec0d0a53ef8","versionType":"git"},{"version":"f53b9b0bdc59c0823679f2e3214e0d538f5951b9","status":"affected","lessThan":"82ef97abf22790182f7d433c74960dfd61b99c33","versionType":"git"},{"version":"f53b9b0bdc59c0823679f2e3214e0d538f5951b9","status":"affected","lessThan":"b7a885ba25960c91db237c3f83b4285156789bce","versionType":"git"},{"version":"f53b9b0bdc59c0823679f2e3214e0d538f5951b9","status":"affected","lessThan":"a0a3ace2a57887dac1e7c9a724846040c3e31868","versionType":"git"},{"version":"f53b9b0bdc59c0823679f2e3214e0d538f5951b9","status":"affected","lessThan":"51e8531371f90bee742c63775c9a568e5d6bf3c5","versionType":"git"},{"version":"f53b9b0bdc59c0823679f2e3214e0d538f5951b9","status":"affected","lessThan":"b32e1590a8d22cf7d7f965e46d5576051acf8e42","versionType":"git"},{"version":"f53b9b0bdc59c0823679f2e3214e0d538f5951b9","status":"affected","lessThan":"91a79b792204313153e1bdbbe5acbfc28903b3a5","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv4/netfilter/nf_reject_ipv4.c","net/ipv6/netfilter/nf_reject_ipv6.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.9","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.9","versionType":"semver"},{"version":"5.10.241","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.190","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.149","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.103","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.44","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.16.4","status":"unaffected","lessThanOrEqual":"6.16.*","versionType":"semver"},{"version":"6.17","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv4/netfilter/nf_reject_ipv4.c","net/ipv6/netfilter/nf_reject_ipv6.c"]}],"references":["https://git.kernel.org/stable/c/7b8b503c06274ef3c6c1a107743f1ec0d0a53ef8","https://git.kernel.org/stable/c/82ef97abf22790182f7d433c74960dfd61b99c33","https://git.kernel.org/stable/c/b7a885ba25960c91db237c3f83b4285156789bce","https://git.kernel.org/stable/c/a0a3ace2a57887dac1e7c9a724846040c3e31868","https://git.kernel.org/stable/c/51e8531371f90bee742c63775c9a568e5d6bf3c5","https://git.kernel.org/stable/c/b32e1590a8d22cf7d7f965e46d5576051acf8e42","https://git.kernel.org/stable/c/91a79b792204313153e1bdbbe5acbfc28903b3a5","https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html","https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html","https://cert-portal.siemens.com/productcert/html/ssa-032379.html","https://cert-portal.siemens.com/productcert/html/ssa-019113.html","https://cert-portal.siemens.com/productcert/html/ssa-457936.html"],"weaknesses":[],"ingestedAt":"2026-10-29T20:09:09.358Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/38xxx/CVE-2025-38732.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-38732","state":"PUBLISHED","datePublished":"2025-09-05T17:20:31.934Z","dateUpdated":"2026-10-15T01:07:52.848Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-04-16T04:51:24.033Z"},"containers":{"cna":{"title":"netfilter: nf_reject: don't leak dst refcount for loopback packets","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_reject: don't leak dst refcount for loopback packets\n\nrecent patches to add a WARN() when replacing skb dst entry found an\nold bug:\n\nWARNING: include/linux/skbuff.h:1165 skb_dst_check_unset include/linux/skbuff.h:1164 [inline]\nWARNING: include/linux/skbuff.h:1165 skb_dst_set include/linux/skbuff.h:1210 [inline]\nWARNING: include/linux/skbuff.h:1165 nf_reject_fill_skb_dst+0x2a4/0x330 net/ipv4/netfilter/nf_reject_ipv4.c:234\n[..]\nCall Trace:\n nf_send_unreach+0x17b/0x6e0 net/ipv4/netfilter/nf_reject_ipv4.c:325\n nft_reject_inet_eval+0x4bc/0x690 net/netfilter/nft_reject_inet.c:27\n expr_call_ops_eval net/netfilter/nf_tables_core.c:237 [inline]\n ..\n\nThis is because blamed commit forgot about loopback packets.\nSuch packets already have a dst_entry attached, even at PRE_ROUTING stage.\n\nInstead of checking hook just check if the skb already has a route\nattached to it."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"f53b9b0bdc59c0823679f2e3214e0d538f5951b9","status":"affected","lessThan":"7b8b503c06274ef3c6c1a107743f1ec0d0a53ef8","versionType":"git"},{"version":"f53b9b0bdc59c0823679f2e3214e0d538f5951b9","status":"affected","lessThan":"82ef97abf22790182f7d433c74960dfd61b99c33","versionType":"git"},{"version":"f53b9b0bdc59c0823679f2e3214e0d538f5951b9","status":"affected","lessThan":"b7a885ba25960c91db237c3f83b4285156789bce","versionType":"git"},{"version":"f53b9b0bdc59c0823679f2e3214e0d538f5951b9","status":"affected","lessThan":"a0a3ace2a57887dac1e7c9a724846040c3e31868","versionType":"git"},{"version":"f53b9b0bdc59c0823679f2e3214e0d538f5951b9","status":"affected","lessThan":"51e8531371f90bee742c63775c9a568e5d6bf3c5","versionType":"git"},{"version":"f53b9b0bdc59c0823679f2e3214e0d538f5951b9","status":"affected","lessThan":"b32e1590a8d22cf7d7f965e46d5576051acf8e42","versionType":"git"},{"version":"f53b9b0bdc59c0823679f2e3214e0d538f5951b9","status":"affected","lessThan":"91a79b792204313153e1bdbbe5acbfc28903b3a5","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv4/netfilter/nf_reject_ipv4.c","net/ipv6/netfilter/nf_reject_ipv6.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.9","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.9","versionType":"semver"},{"version":"5.10.241","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.190","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.149","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.103","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.44","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.16.4","status":"unaffected","lessThanOrEqual":"6.16.*","versionType":"semver"},{"version":"6.17","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/ipv4/netfilter/nf_reject_ipv4.c","net/ipv6/netfilter/nf_reject_ipv6.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/7b8b503c06274ef3c6c1a107743f1ec0d0a53ef8"},{"url":"https://git.kernel.org/stable/c/82ef97abf22790182f7d433c74960dfd61b99c33"},{"url":"https://git.kernel.org/stable/c/b7a885ba25960c91db237c3f83b4285156789bce"},{"url":"https://git.kernel.org/stable/c/a0a3ace2a57887dac1e7c9a724846040c3e31868"},{"url":"https://git.kernel.org/stable/c/51e8531371f90bee742c63775c9a568e5d6bf3c5"},{"url":"https://git.kernel.org/stable/c/b32e1590a8d22cf7d7f965e46d5576051acf8e42"},{"url":"https://git.kernel.org/stable/c/91a79b792204313153e1bdbbe5acbfc28903b3a5"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T21:33:54.815Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"5.10.241"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"5.15.190"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.1.149"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.6.103"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.12.44"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.16.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.9","versionEndExcluding":"6.17"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CVE Program Container","references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"},{"url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html"}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2025-11-03T17:42:03.823Z"}},{"affected":[{"vendor":"Siemens","product":"SIMATIC CN 4100","defaultStatus":"unknown","versions":[{"version":"0","status":"affected","lessThan":"V5.0","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.6","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.7","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.6","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.7","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.6","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.7","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.6","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.7","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIPLUS S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.6","status":"affected","lessThan":"*","versionType":"custom"}]},{"vendor":"Siemens","product":"SIPLUS S7-1500 CPU 1518-4 PN/DP MFP","defaultStatus":"unknown","versions":[{"version":"V3.1.7","status":"affected","lessThan":"*","versionType":"custom"}]}],"references":[{"url":"https://cert-portal.siemens.com/productcert/html/ssa-032379.html"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-019113.html"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-457936.html"}],"providerMetadata":{"shortName":"siemens-SADP","orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","dateUpdated":"2026-10-15T01:07:52.848Z"},"x_adpType":"supplier"}]}}}