CVE-2025-38476 (GCVE-0-2025-38476)

Vulnerability from cvelistv5 – Published: 2025-07-28 11:21 – Updated: 2026-08-05 12:02
VLAI
Title
rpl: Fix use-after-free in rpl_do_srh_inline().
Summary
In the Linux kernel, the following vulnerability has been resolved: rpl: Fix use-after-free in rpl_do_srh_inline(). Running lwt_dst_cache_ref_loop.sh in selftest with KASAN triggers the splat below [0]. rpl_do_srh_inline() fetches ipv6_hdr(skb) and accesses it after skb_cow_head(), which is illegal as the header could be freed then. Let's fix it by making oldhdr to a local struct instead of a pointer. [0]: [root@fedora net]# ./lwt_dst_cache_ref_loop.sh ... TEST: rpl (input) [ 57.631529] ================================================================== BUG: KASAN: slab-use-after-free in rpl_do_srh_inline.isra.0 (net/ipv6/rpl_iptunnel.c:174) Read of size 40 at addr ffff888122bf96d8 by task ping6/1543 CPU: 50 UID: 0 PID: 1543 Comm: ping6 Not tainted 6.16.0-rc5-01302-gfadd1e6231b1 #23 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: <IRQ> dump_stack_lvl (lib/dump_stack.c:122) print_report (mm/kasan/report.c:409 mm/kasan/report.c:521) kasan_report (mm/kasan/report.c:221 mm/kasan/report.c:636) kasan_check_range (mm/kasan/generic.c:175 (discriminator 1) mm/kasan/generic.c:189 (discriminator 1)) __asan_memmove (mm/kasan/shadow.c:94 (discriminator 2)) rpl_do_srh_inline.isra.0 (net/ipv6/rpl_iptunnel.c:174) rpl_input (net/ipv6/rpl_iptunnel.c:201 net/ipv6/rpl_iptunnel.c:282) lwtunnel_input (net/core/lwtunnel.c:459) ipv6_rcv (./include/net/dst.h:471 (discriminator 1) ./include/net/dst.h:469 (discriminator 1) net/ipv6/ip6_input.c:79 (discriminator 1) ./include/linux/netfilter.h:317 (discriminator 1) ./include/linux/netfilter.h:311 (discriminator 1) net/ipv6/ip6_input.c:311 (discriminator 1)) __netif_receive_skb_one_core (net/core/dev.c:5967) process_backlog (./include/linux/rcupdate.h:869 net/core/dev.c:6440) __napi_poll.constprop.0 (net/core/dev.c:7452) net_rx_action (net/core/dev.c:7518 net/core/dev.c:7643) handle_softirqs (kernel/softirq.c:579) do_softirq (kernel/softirq.c:480 (discriminator 20)) </IRQ> <TASK> __local_bh_enable_ip (kernel/softirq.c:407) __dev_queue_xmit (net/core/dev.c:4740) ip6_finish_output2 (./include/linux/netdevice.h:3358 ./include/net/neighbour.h:526 ./include/net/neighbour.h:540 net/ipv6/ip6_output.c:141) ip6_finish_output (net/ipv6/ip6_output.c:215 net/ipv6/ip6_output.c:226) ip6_output (./include/linux/netfilter.h:306 net/ipv6/ip6_output.c:248) ip6_send_skb (net/ipv6/ip6_output.c:1983) rawv6_sendmsg (net/ipv6/raw.c:588 net/ipv6/raw.c:918) __sys_sendto (net/socket.c:714 (discriminator 1) net/socket.c:729 (discriminator 1) net/socket.c:2228 (discriminator 1)) __x64_sys_sendto (net/socket.c:2231) do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1)) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) RIP: 0033:0x7f68cffb2a06 Code: 5d e8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 75 19 83 e2 39 83 fa 08 75 11 e8 26 ff ff ff 66 0f 1f 44 00 00 48 8b 45 10 0f 05 <48> 8b 5d f8 c9 c3 0f 1f 40 00 f3 0f 1e fa 55 48 89 e5 48 83 ec 08 RSP: 002b:00007ffefb7c53d0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000564cd69f10a0 RCX: 00007f68cffb2a06 RDX: 0000000000000040 RSI: 0000564cd69f10a4 RDI: 0000000000000003 RBP: 00007ffefb7c53f0 R08: 0000564cd6a032ac R09: 000000000000001c R10: 0000000000000000 R11: 0000000000000202 R12: 0000564cd69f10a4 R13: 0000000000000040 R14: 00007ffefb7c66e0 R15: 0000564cd69f10a0 </TASK> Allocated by task 1543: kasan_save_stack (mm/kasan/common.c:48) kasan_save_track (mm/kasan/common.c:60 (discriminator 1) mm/kasan/common.c:69 (discriminator 1)) __kasan_slab_alloc (mm/kasan/common.c:319 mm/kasan/common.c:345) kmem_cache_alloc_node_noprof (./include/linux/kasan.h:250 mm/slub.c:4148 mm/slub.c:4197 mm/slub.c:4249) kmalloc_reserve (net/core/skbuff.c:581 (discriminator 88)) __alloc_skb (net/core/skbuff.c:669) __ip6_append_data (net/ipv6/ip6_output.c:1672 (discriminator 1)) ip6_ ---truncated---
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: a7a29f9c361f8542604ef959ae6627f423b7a412 , < c09e21dfc08d8afb92d9ea3bee3457adbe3ef297 (git)
Affected: a7a29f9c361f8542604ef959ae6627f423b7a412 , < 8ba6c2362b85089b8972ac5f20b24fc71a4b8ffc (git)
Affected: a7a29f9c361f8542604ef959ae6627f423b7a412 , < e8101506ab86dd78f823b7028f2036a380f3a12a (git)
Affected: a7a29f9c361f8542604ef959ae6627f423b7a412 , < 62dcd9d6e61c39122d2f251a26829e2e55b0a11d (git)
Affected: a7a29f9c361f8542604ef959ae6627f423b7a412 , < 06ec83b6c792fde1f710c1de3e836da6e257c4c4 (git)
Affected: a7a29f9c361f8542604ef959ae6627f423b7a412 , < 034b428aa3583373a5a20b1c5931bb2b3cae1f36 (git)
Affected: a7a29f9c361f8542604ef959ae6627f423b7a412 , < b640daa2822a39ff76e70200cb2b7b892b896dce (git)
Create a notification for this product.
Linux Linux Affected: 5.7
Unaffected: 0 , < 5.7 (semver)
Unaffected: 5.10.241 , ≤ 5.10.* (semver)
Unaffected: 5.15.190 , ≤ 5.15.* (semver)
Unaffected: 6.1.147 , ≤ 6.1.* (semver)
Unaffected: 6.6.100 , ≤ 6.6.* (semver)
Unaffected: 6.12.40 , ≤ 6.12.* (semver)
Unaffected: 6.15.8 , ≤ 6.15.* (semver)
Unaffected: 6.16 , ≤ * (original_commit_for_fix)
Create a notification for this product.
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      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrpl: Fix use-after-free in rpl_do_srh_inline().\n\nRunning lwt_dst_cache_ref_loop.sh in selftest with KASAN triggers\nthe splat below [0].\n\nrpl_do_srh_inline() fetches ipv6_hdr(skb) and accesses it after\nskb_cow_head(), which is illegal as the header could be freed then.\n\nLet\u0027s fix it by making oldhdr to a local struct instead of a pointer.\n\n[0]:\n[root@fedora net]# ./lwt_dst_cache_ref_loop.sh\n...\nTEST: rpl (input)\n[   57.631529] ==================================================================\nBUG: KASAN: slab-use-after-free in rpl_do_srh_inline.isra.0 (net/ipv6/rpl_iptunnel.c:174)\nRead of size 40 at addr ffff888122bf96d8 by task ping6/1543\n\nCPU: 50 UID: 0 PID: 1543 Comm: ping6 Not tainted 6.16.0-rc5-01302-gfadd1e6231b1 #23 PREEMPT(voluntary)\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\nCall Trace:\n \u003cIRQ\u003e\n dump_stack_lvl (lib/dump_stack.c:122)\n print_report (mm/kasan/report.c:409 mm/kasan/report.c:521)\n kasan_report (mm/kasan/report.c:221 mm/kasan/report.c:636)\n kasan_check_range (mm/kasan/generic.c:175 (discriminator 1) mm/kasan/generic.c:189 (discriminator 1))\n __asan_memmove (mm/kasan/shadow.c:94 (discriminator 2))\n rpl_do_srh_inline.isra.0 (net/ipv6/rpl_iptunnel.c:174)\n rpl_input (net/ipv6/rpl_iptunnel.c:201 net/ipv6/rpl_iptunnel.c:282)\n lwtunnel_input (net/core/lwtunnel.c:459)\n ipv6_rcv (./include/net/dst.h:471 (discriminator 1) ./include/net/dst.h:469 (discriminator 1) net/ipv6/ip6_input.c:79 (discriminator 1) ./include/linux/netfilter.h:317 (discriminator 1) ./include/linux/netfilter.h:311 (discriminator 1) net/ipv6/ip6_input.c:311 (discriminator 1))\n __netif_receive_skb_one_core (net/core/dev.c:5967)\n process_backlog (./include/linux/rcupdate.h:869 net/core/dev.c:6440)\n __napi_poll.constprop.0 (net/core/dev.c:7452)\n net_rx_action (net/core/dev.c:7518 net/core/dev.c:7643)\n handle_softirqs (kernel/softirq.c:579)\n do_softirq (kernel/softirq.c:480 (discriminator 20))\n \u003c/IRQ\u003e\n \u003cTASK\u003e\n __local_bh_enable_ip (kernel/softirq.c:407)\n __dev_queue_xmit (net/core/dev.c:4740)\n ip6_finish_output2 (./include/linux/netdevice.h:3358 ./include/net/neighbour.h:526 ./include/net/neighbour.h:540 net/ipv6/ip6_output.c:141)\n ip6_finish_output (net/ipv6/ip6_output.c:215 net/ipv6/ip6_output.c:226)\n ip6_output (./include/linux/netfilter.h:306 net/ipv6/ip6_output.c:248)\n ip6_send_skb (net/ipv6/ip6_output.c:1983)\n rawv6_sendmsg (net/ipv6/raw.c:588 net/ipv6/raw.c:918)\n __sys_sendto (net/socket.c:714 (discriminator 1) net/socket.c:729 (discriminator 1) net/socket.c:2228 (discriminator 1))\n __x64_sys_sendto (net/socket.c:2231)\n do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1))\n entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)\nRIP: 0033:0x7f68cffb2a06\nCode: 5d e8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 75 19 83 e2 39 83 fa 08 75 11 e8 26 ff ff ff 66 0f 1f 44 00 00 48 8b 45 10 0f 05 \u003c48\u003e 8b 5d f8 c9 c3 0f 1f 40 00 f3 0f 1e fa 55 48 89 e5 48 83 ec 08\nRSP: 002b:00007ffefb7c53d0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c\nRAX: ffffffffffffffda RBX: 0000564cd69f10a0 RCX: 00007f68cffb2a06\nRDX: 0000000000000040 RSI: 0000564cd69f10a4 RDI: 0000000000000003\nRBP: 00007ffefb7c53f0 R08: 0000564cd6a032ac R09: 000000000000001c\nR10: 0000000000000000 R11: 0000000000000202 R12: 0000564cd69f10a4\nR13: 0000000000000040 R14: 00007ffefb7c66e0 R15: 0000564cd69f10a0\n \u003c/TASK\u003e\n\nAllocated by task 1543:\n kasan_save_stack (mm/kasan/common.c:48)\n kasan_save_track (mm/kasan/common.c:60 (discriminator 1) mm/kasan/common.c:69 (discriminator 1))\n __kasan_slab_alloc (mm/kasan/common.c:319 mm/kasan/common.c:345)\n kmem_cache_alloc_node_noprof (./include/linux/kasan.h:250 mm/slub.c:4148 mm/slub.c:4197 mm/slub.c:4249)\n kmalloc_reserve (net/core/skbuff.c:581 (discriminator 88))\n __alloc_skb (net/core/skbuff.c:669)\n __ip6_append_data (net/ipv6/ip6_output.c:1672 (discriminator 1))\n ip6_\n---truncated---"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - The vulnerable function is reached from `rpl_input()` via `lwtunnel_input()` off `ipv6_rcv()`, i.e. driven purely by IPv6 packets received from a remote peer on a node with an `encap rpl` route (the KASAN stack confirms the `ipv6_rcv` \u2192 `lwtunnel_input` \u2192 `rpl_input` path). No local access is needed.\nAC:L - `skb_cow_head()` unconditionally reallocates whenever the compressed SRH plus link-layer overhead exceeds the skb\u0027s headroom \u2014 which a normal multi-segment RPL route always does \u2014 or whenever the skb header is cloned, so every matching packet trips the use-after-free with no race to win and no attacker-uncontrollable memory layout requirement.\nPR:N - The attacker only needs to send an IPv6 packet toward the RPL-routed prefix; there is no authentication, credential, or capability check anywhere on the receive path. The route configuration is victim-side administrative state, not a privilege the attacker must hold.\nUI:N - Processing happens in softirq context during normal packet reception and forwarding; no action by any local user or administrator is required at exploitation time.\nS:U - The freed memory and the resulting corruption are both within the kernel\u0027s own security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - Up to 40 bytes of freed slab memory are copied into the outgoing packet header, and roughly 21 of those bytes (traffic class, flow label, hop limit, and the entire 16-byte source address) survive to be transmitted on the wire, giving a directly observable kernel heap disclosure; the general use-after-free read primitive over attacker-groomable slab contents also warrants High.\nI:H - The use-after-free lets reallocated, attacker-sprayed heap contents dictate the constructed IPv6 header of a forwarded packet, and per kernel UAF guidance such freed-object reuse is treated as exploitable for heap manipulation and control-flow corruption rather than a benign read.\nA:H - Reading a freed skb head can hit poisoned, reallocated, or unmapped memory and oopses immediately under KASAN/debug allocators, and the resulting malformed headers occur in softirq context on the forwarding path \u2014 any such crash panics the router."
            }
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        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:02:13.331Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/c09e21dfc08d8afb92d9ea3bee3457adbe3ef297"
        },
        {
          "url": "https://git.kernel.org/stable/c/8ba6c2362b85089b8972ac5f20b24fc71a4b8ffc"
        },
        {
          "url": "https://git.kernel.org/stable/c/e8101506ab86dd78f823b7028f2036a380f3a12a"
        },
        {
          "url": "https://git.kernel.org/stable/c/62dcd9d6e61c39122d2f251a26829e2e55b0a11d"
        },
        {
          "url": "https://git.kernel.org/stable/c/06ec83b6c792fde1f710c1de3e836da6e257c4c4"
        },
        {
          "url": "https://git.kernel.org/stable/c/034b428aa3583373a5a20b1c5931bb2b3cae1f36"
        },
        {
          "url": "https://git.kernel.org/stable/c/b640daa2822a39ff76e70200cb2b7b892b896dce"
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      ],
      "title": "rpl: Fix use-after-free in rpl_do_srh_inline().",
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    "assignerShortName": "Linux",
    "cveId": "CVE-2025-38476",
    "datePublished": "2025-07-28T11:21:37.175Z",
    "dateReserved": "2025-04-16T04:51:24.021Z",
    "dateUpdated": "2026-08-05T12:02:13.331Z",
    "state": "PUBLISHED"
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  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2025-38476",
      "date": "2026-08-06",
      "epss": "0.00325",
      "percentile": "0.24915"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2025-38476\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2025-07-28T12:15:29.483\",\"lastModified\":\"2026-07-30T06:23:19.587\",\"vulnStatus\":\"Modified\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nrpl: Fix use-after-free in rpl_do_srh_inline().\\n\\nRunning lwt_dst_cache_ref_loop.sh in selftest with KASAN triggers\\nthe splat below [0].\\n\\nrpl_do_srh_inline() fetches ipv6_hdr(skb) and accesses it after\\nskb_cow_head(), which is illegal as the header could be freed then.\\n\\nLet\u0027s fix it by making oldhdr to a local struct instead of a pointer.\\n\\n[0]:\\n[root@fedora net]# ./lwt_dst_cache_ref_loop.sh\\n...\\nTEST: rpl (input)\\n[   57.631529] ==================================================================\\nBUG: KASAN: slab-use-after-free in rpl_do_srh_inline.isra.0 (net/ipv6/rpl_iptunnel.c:174)\\nRead of size 40 at addr ffff888122bf96d8 by task ping6/1543\\n\\nCPU: 50 UID: 0 PID: 1543 Comm: ping6 Not tainted 6.16.0-rc5-01302-gfadd1e6231b1 #23 PREEMPT(voluntary)\\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014\\nCall Trace:\\n \u003cIRQ\u003e\\n dump_stack_lvl (lib/dump_stack.c:122)\\n print_report (mm/kasan/report.c:409 mm/kasan/report.c:521)\\n kasan_report (mm/kasan/report.c:221 mm/kasan/report.c:636)\\n kasan_check_range (mm/kasan/generic.c:175 (discriminator 1) mm/kasan/generic.c:189 (discriminator 1))\\n __asan_memmove (mm/kasan/shadow.c:94 (discriminator 2))\\n rpl_do_srh_inline.isra.0 (net/ipv6/rpl_iptunnel.c:174)\\n rpl_input (net/ipv6/rpl_iptunnel.c:201 net/ipv6/rpl_iptunnel.c:282)\\n lwtunnel_input (net/core/lwtunnel.c:459)\\n ipv6_rcv (./include/net/dst.h:471 (discriminator 1) ./include/net/dst.h:469 (discriminator 1) net/ipv6/ip6_input.c:79 (discriminator 1) ./include/linux/netfilter.h:317 (discriminator 1) ./include/linux/netfilter.h:311 (discriminator 1) net/ipv6/ip6_input.c:311 (discriminator 1))\\n __netif_receive_skb_one_core (net/core/dev.c:5967)\\n process_backlog (./include/linux/rcupdate.h:869 net/core/dev.c:6440)\\n __napi_poll.constprop.0 (net/core/dev.c:7452)\\n net_rx_action (net/core/dev.c:7518 net/core/dev.c:7643)\\n handle_softirqs (kernel/softirq.c:579)\\n do_softirq (kernel/softirq.c:480 (discriminator 20))\\n \u003c/IRQ\u003e\\n \u003cTASK\u003e\\n __local_bh_enable_ip (kernel/softirq.c:407)\\n __dev_queue_xmit (net/core/dev.c:4740)\\n ip6_finish_output2 (./include/linux/netdevice.h:3358 ./include/net/neighbour.h:526 ./include/net/neighbour.h:540 net/ipv6/ip6_output.c:141)\\n ip6_finish_output (net/ipv6/ip6_output.c:215 net/ipv6/ip6_output.c:226)\\n ip6_output (./include/linux/netfilter.h:306 net/ipv6/ip6_output.c:248)\\n ip6_send_skb (net/ipv6/ip6_output.c:1983)\\n rawv6_sendmsg (net/ipv6/raw.c:588 net/ipv6/raw.c:918)\\n __sys_sendto (net/socket.c:714 (discriminator 1) net/socket.c:729 (discriminator 1) net/socket.c:2228 (discriminator 1))\\n __x64_sys_sendto (net/socket.c:2231)\\n do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1))\\n entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)\\nRIP: 0033:0x7f68cffb2a06\\nCode: 5d e8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 75 19 83 e2 39 83 fa 08 75 11 e8 26 ff ff ff 66 0f 1f 44 00 00 48 8b 45 10 0f 05 \u003c48\u003e 8b 5d f8 c9 c3 0f 1f 40 00 f3 0f 1e fa 55 48 89 e5 48 83 ec 08\\nRSP: 002b:00007ffefb7c53d0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c\\nRAX: ffffffffffffffda RBX: 0000564cd69f10a0 RCX: 00007f68cffb2a06\\nRDX: 0000000000000040 RSI: 0000564cd69f10a4 RDI: 0000000000000003\\nRBP: 00007ffefb7c53f0 R08: 0000564cd6a032ac R09: 000000000000001c\\nR10: 0000000000000000 R11: 0000000000000202 R12: 0000564cd69f10a4\\nR13: 0000000000000040 R14: 00007ffefb7c66e0 R15: 0000564cd69f10a0\\n \u003c/TASK\u003e\\n\\nAllocated by task 1543:\\n kasan_save_stack (mm/kasan/common.c:48)\\n kasan_save_track (mm/kasan/common.c:60 (discriminator 1) mm/kasan/common.c:69 (discriminator 1))\\n __kasan_slab_alloc (mm/kasan/common.c:319 mm/kasan/common.c:345)\\n kmem_cache_alloc_node_noprof (./include/linux/kasan.h:250 mm/slub.c:4148 mm/slub.c:4197 mm/slub.c:4249)\\n kmalloc_reserve (net/core/skbuff.c:581 (discriminator 88))\\n __alloc_skb (net/core/skbuff.c:669)\\n __ip6_append_data (net/ipv6/ip6_output.c:1672 (discriminator 1))\\n ip6_\\n---truncated---\"},{\"lang\":\"es\",\"value\":\"En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: rpl: Se corrige el problema de use-after-free en rpl_do_srh_inline(). Ejecutar lwt_dst_cache_ref_loop.sh en autoprueba con KASAN activa el splat debajo de [0]. rpl_do_srh_inline() recupera ipv6_hdr(skb) y accede a \u00e9l despu\u00e9s de skb_cow_head(), lo cual es ilegal, ya que la cabecera podr\u00eda liberarse en ese momento. Para solucionarlo, convertimos oldhdr en una estructura local en lugar de un puntero. [0]: [root@fedora net]# ./lwt_dst_cache_ref_loop.sh ... TEST: rpl (input) [ 57.631529] ================================================================== BUG: KASAN: slab-use-after-free in rpl_do_srh_inline.isra.0 (net/ipv6/rpl_iptunnel.c:174) Read of size 40 at addr ffff888122bf96d8 by task ping6/1543 CPU: 50 UID: 0 PID: 1543 Comm: ping6 Not tainted 6.16.0-rc5-01302-gfadd1e6231b1 #23 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace:  dump_stack_lvl (lib/dump_stack.c:122) print_report (mm/kasan/report.c:409 mm/kasan/report.c:521) kasan_report (mm/kasan/report.c:221 mm/kasan/report.c:636) kasan_check_range (mm/kasan/generic.c:175 (discriminator 1) mm/kasan/generic.c:189 (discriminator 1)) __asan_memmove (mm/kasan/shadow.c:94 (discriminator 2)) rpl_do_srh_inline.isra.0 (net/ipv6/rpl_iptunnel.c:174) rpl_input (net/ipv6/rpl_iptunnel.c:201 net/ipv6/rpl_iptunnel.c:282) lwtunnel_input (net/core/lwtunnel.c:459) ipv6_rcv (./include/net/dst.h:471 (discriminator 1) ./include/net/dst.h:469 (discriminator 1) net/ipv6/ip6_input.c:79 (discriminator 1) ./include/linux/netfilter.h:317 (discriminator 1) ./include/linux/netfilter.h:311 (discriminator 1) net/ipv6/ip6_input.c:311 (discriminator 1)) __netif_receive_skb_one_core (net/core/dev.c:5967) process_backlog (./include/linux/rcupdate.h:869 net/core/dev.c:6440) __napi_poll.constprop.0 (net/core/dev.c:7452) net_rx_action (net/core/dev.c:7518 net/core/dev.c:7643) handle_softirqs (kernel/softirq.c:579) do_softirq (kernel/softirq.c:480 (discriminator 20))   __local_bh_enable_ip (kernel/softirq.c:407) __dev_queue_xmit (net/core/dev.c:4740) ip6_finish_output2 (./include/linux/netdevice.h:3358 ./include/net/neighbour.h:526 ./include/net/neighbour.h:540 net/ipv6/ip6_output.c:141) ip6_finish_output (net/ipv6/ip6_output.c:215 net/ipv6/ip6_output.c:226) ip6_output (./include/linux/netfilter.h:306 net/ipv6/ip6_output.c:248) ip6_send_skb (net/ipv6/ip6_output.c:1983) rawv6_sendmsg (net/ipv6/raw.c:588 net/ipv6/raw.c:918) __sys_sendto (net/socket.c:714 (discriminator 1) net/socket.c:729 (discriminator 1) net/socket.c:2228 (discriminator 1)) __x64_sys_sendto (net/socket.c:2231) do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1)) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) RIP: 0033:0x7f68cffb2a06 Code: 5d e8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 75 19 83 e2 39 83 fa 08 75 11 e8 26 ff ff ff 66 0f 1f 44 00 00 48 8b 45 10 0f 05 \u0026lt;48\u0026gt; 8b 5d f8 c9 c3 0f 1f 40 00 f3 0f 1e fa 55 48 89 e5 48 83 ec 08 RSP: 002b:00007ffefb7c53d0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000564cd69f10a0 RCX: 00007f68cffb2a06 RDX: 0000000000000040 RSI: 0000564cd69f10a4 RDI: 0000000000000003 RBP: 00007ffefb7c53f0 R08: 0000564cd6a032ac R09: 000000000000001c R10: 0000000000000000 R11: 0000000000000202 R12: 0000564cd69f10a4 R13: 0000000000000040 R14: 00007ffefb7c66e0 R15: 0000564cd69f10a0  Allocated by task 1543: kasan_save_stack (mm/kasan/common.c:48) kasan_save_track (mm/kasan/common.c:60 (discriminator 1) mm/kasan/common.c:69 (discriminator 1)) __kasan_slab_alloc (mm/kasan/common.c:319 mm/kasan/common.c:345) kmem_cache_alloc_node_noprof (./include/linux/kasan.h:250 mm/slub.c:4148 mm/slub.c:4197 mm/slub.c:4249) kmalloc_reserve (net/core/skbuff.c:581 (discriminator 88)) __alloc_skb (net/core/skbuff.c:669) __ip6_append_data (net/ipv6/ip6_output.c:1672 (discriminator 1)) ip6_ ---truncated---\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"net/ipv6/rpl_iptunnel.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"a7a29f9c361f8542604ef959ae6627f423b7a412\",\"lessThan\":\"c09e21dfc08d8afb92d9ea3bee3457adbe3ef297\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a7a29f9c361f8542604ef959ae6627f423b7a412\",\"lessThan\":\"8ba6c2362b85089b8972ac5f20b24fc71a4b8ffc\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a7a29f9c361f8542604ef959ae6627f423b7a412\",\"lessThan\":\"e8101506ab86dd78f823b7028f2036a380f3a12a\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a7a29f9c361f8542604ef959ae6627f423b7a412\",\"lessThan\":\"62dcd9d6e61c39122d2f251a26829e2e55b0a11d\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a7a29f9c361f8542604ef959ae6627f423b7a412\",\"lessThan\":\"06ec83b6c792fde1f710c1de3e836da6e257c4c4\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a7a29f9c361f8542604ef959ae6627f423b7a412\",\"lessThan\":\"034b428aa3583373a5a20b1c5931bb2b3cae1f36\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a7a29f9c361f8542604ef959ae6627f423b7a412\",\"lessThan\":\"b640daa2822a39ff76e70200cb2b7b892b896dce\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"net/ipv6/rpl_iptunnel.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"5.7\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"5.7\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.10.241\",\"lessThanOrEqual\":\"5.10.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"5.15.190\",\"lessThanOrEqual\":\"5.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.147\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.100\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.40\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.15.8\",\"lessThanOrEqual\":\"6.15.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.16\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":9.8,\"baseSeverity\":\"CRITICAL\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":3.9,\"impactScore\":5.9},{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\",\"baseScore\":7.8,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9}]},\"weaknesses\":[{\"source\":\"nvd@nist.gov\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-416\"}]}],\"configurations\":[{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.7\",\"versionEndExcluding\":\"5.10.241\",\"matchCriteriaId\":\"FE1D1811-AF6C-47BE-9560-6B15EFD7278D\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.11\",\"versionEndExcluding\":\"5.15.190\",\"matchCriteriaId\":\"AD9E597F-3DDE-4D7E-976C-463D0611F13F\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"5.16\",\"versionEndExcluding\":\"6.1.147\",\"matchCriteriaId\":\"A4FD62FC-0DAE-4ACE-8C9C-66156518C3E1\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.2\",\"versionEndExcluding\":\"6.6.100\",\"matchCriteriaId\":\"094B81E0-B756-4727-85CA-F3F8D1C9D116\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.7\",\"versionEndExcluding\":\"6.12.40\",\"matchCriteriaId\":\"0099D5A4-B157-4D36-8858-982C7D579030\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\",\"versionStartIncluding\":\"6.13\",\"versionEndExcluding\":\"6.15.8\",\"matchCriteriaId\":\"C7AFE5B0-F3B1-4D30-B8BF-EDA0385C4746\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.16:rc1:*:*:*:*:*:*\",\"matchCriteriaId\":\"6D4894DB-CCFE-4602-B1BF-3960B2E19A01\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.16:rc2:*:*:*:*:*:*\",\"matchCriteriaId\":\"09709862-E348-4378-8632-5A7813EDDC86\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.16:rc3:*:*:*:*:*:*\",\"matchCriteriaId\":\"415BF58A-8197-43F5-B3D7-D1D63057A26E\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.16:rc4:*:*:*:*:*:*\",\"matchCriteriaId\":\"A0517869-312D-4429-80C2-561086E1421C\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.16:rc5:*:*:*:*:*:*\",\"matchCriteriaId\":\"85421F4E-C863-4ABF-B4B4-E887CC2F7F92\"},{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:linux:linux_kernel:6.16:rc6:*:*:*:*:*:*\",\"matchCriteriaId\":\"3827F0D4-5FEE-4181-B267-5A45E7CA11FC\"}]}]},{\"nodes\":[{\"operator\":\"OR\",\"negate\":false,\"cpeMatch\":[{\"vulnerable\":true,\"criteria\":\"cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*\",\"matchCriteriaId\":\"FA6FEEC2-9F11-4643-8827-749718254FED\"}]}]}],\"references\":[{\"url\":\"https://git.kernel.org/stable/c/034b428aa3583373a5a20b1c5931bb2b3cae1f36\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/06ec83b6c792fde1f710c1de3e836da6e257c4c4\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/62dcd9d6e61c39122d2f251a26829e2e55b0a11d\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/8ba6c2362b85089b8972ac5f20b24fc71a4b8ffc\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/b640daa2822a39ff76e70200cb2b7b892b896dce\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/c09e21dfc08d8afb92d9ea3bee3457adbe3ef297\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://git.kernel.org/stable/c/e8101506ab86dd78f823b7028f2036a380f3a12a\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"tags\":[\"Patch\"]},{\"url\":\"https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Third Party Advisory\"]},{\"url\":\"https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html\",\"source\":\"af854a3a-2127-422b-91ae-364da2661108\",\"tags\":[\"Third Party Advisory\"]}]}}",
    "redhat_vex": {
      "aggregate_severity": "None",
      "current_release_date": "2026-06-30T10:33:17+00:00",
      "cve": "CVE-2025-38476",
      "id": "CVE-2025-38476",
      "initial_release_date": "2025-07-28T00:00:00+00:00",
      "product_status:known_not_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: rpl: Fix use-after-free in rpl_do_srh_inline()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-38476.json",
      "version": "3"
    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.