CVE-2025-38476
rpl: Fix use-after-free in rpl_do_srh_inline().
Description
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---
INFO
Published Date :
July 28, 2025, 12:15 p.m.
Last Modified :
Dec. 22, 2025, 7:28 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update the Linux kernel to include the fix.
- Recompile the kernel with the provided patch.
- Apply the patch to the kernel source code.
- Test the system after applying the fix.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2025-38476.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2025-38476 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2025-38476
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2025-38476 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2025-38476 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Dec. 22, 2025
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Added CWE CWE-416 Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:6.16:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.11 up to (excluding) 5.15.190 *cpe:2.3:o:linux:linux_kernel:6.16:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.16:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.16:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:6.16:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.13 up to (excluding) 6.15.8 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.7 up to (excluding) 6.12.40 *cpe:2.3:o:linux:linux_kernel:6.16:rc6:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.16 up to (excluding) 6.1.147 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.2 up to (excluding) 6.6.100 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 5.7 up to (excluding) 5.10.241 Added CPE Configuration OR *cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* Added Reference Type kernel.org: https://git.kernel.org/stable/c/034b428aa3583373a5a20b1c5931bb2b3cae1f36 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/06ec83b6c792fde1f710c1de3e836da6e257c4c4 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/62dcd9d6e61c39122d2f251a26829e2e55b0a11d Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/8ba6c2362b85089b8972ac5f20b24fc71a4b8ffc Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/b640daa2822a39ff76e70200cb2b7b892b896dce Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/c09e21dfc08d8afb92d9ea3bee3457adbe3ef297 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/e8101506ab86dd78f823b7028f2036a380f3a12a Types: Patch Added Reference Type CVE: https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html Types: Third Party Advisory Added Reference Type CVE: https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html Types: Third Party Advisory -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Nov. 03, 2025
Action Type Old Value New Value Added Reference https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html Added Reference https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 28, 2025
Action Type Old Value New Value Added Reference https://git.kernel.org/stable/c/8ba6c2362b85089b8972ac5f20b24fc71a4b8ffc Added Reference https://git.kernel.org/stable/c/c09e21dfc08d8afb92d9ea3bee3457adbe3ef297 -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jul. 28, 2025
Action Type Old Value New Value Added Description 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--- Added Reference https://git.kernel.org/stable/c/034b428aa3583373a5a20b1c5931bb2b3cae1f36 Added Reference https://git.kernel.org/stable/c/06ec83b6c792fde1f710c1de3e836da6e257c4c4 Added Reference https://git.kernel.org/stable/c/62dcd9d6e61c39122d2f251a26829e2e55b0a11d Added Reference https://git.kernel.org/stable/c/b640daa2822a39ff76e70200cb2b7b892b896dce Added Reference https://git.kernel.org/stable/c/e8101506ab86dd78f823b7028f2036a380f3a12a