Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
Linux Linux — pfcp: Destroy device along with udp socket's netns dismantle.
AV AC PR UI S C I A CVSS EPSS %ile KEV
L L L N U N N H 5.5 .0018 8.2 —
AFFECTED
Product Versions Fixed
Linux 76c8764ef36a5d37ea2e551bda28ac7f028383ba – —
Linux 6.10 – 6.12.11
TIMELINE
Dec 29 Reserved by Linux
Jan 31 Published (CNA: Linux)
Jul 30 RESCORED — CVE-2025-21677 (Linux). CVSS 7.8 → 5.5 (NVD).
Description
In the Linux kernel, the following vulnerability has been resolved:
pfcp: Destroy device along with udp socket's netns dismantle.
pfcp_newlink() links the device to a list in dev_net(dev) instead
of net, where a udp tunnel socket is created.
Even when net is removed, the device stays alive on dev_net(dev).
Then, removing net triggers the splat below. [0]
In this example, pfcp0 is created in ns2, but the udp socket is
created in ns1.
ip netns add ns1
ip netns add ns2
ip -n ns1 link add netns ns2 name pfcp0 type pfcp
ip netns del ns1
Let's link the device to the socket's netns instead.
Now, pfcp_net_exit() needs another netdev iteration to remove
all pfcp devices in the netns.
pfcp_dev_list is not used under RCU, so the list API is converted
to the non-RCU variant.
pfcp_net_exit() can be converted to .exit_batch_rtnl() in net-next.
[0]:
ref_tracker: net notrefcnt@00000000128b34dc has 1/1 users at
sk_alloc (./include/net/net_namespace.h:345 net/core/sock.c:2236)
inet_create (net/ipv4/af_inet.c:326 net/ipv4/af_inet.c:252)
__sock_create (net/socket.c:1558)
udp_sock_create4 (net/ipv4/udp_tunnel_core.c:18)
pfcp_create_sock (drivers/net/pfcp.c:168)
pfcp_newlink (drivers/net/pfcp.c:182 drivers/net/pfcp.c:197)
rtnl_newlink (net/core/rtnetlink.c:3786 net/core/rtnetlink.c:3897 net/core/rtnetlink.c:4012)
rtnetlink_rcv_msg (net/core/rtnetlink.c:6922)
netlink_rcv_skb (net/netlink/af_netlink.c:2542)
netlink_unicast (net/netlink/af_netlink.c:1321 net/netlink/af_netlink.c:1347)
netlink_sendmsg (net/netlink/af_netlink.c:1891)
____sys_sendmsg (net/socket.c:711 net/socket.c:726 net/socket.c:2583)
___sys_sendmsg (net/socket.c:2639)
__sys_sendmsg (net/socket.c:2669)
do_syscall_64 (arch/x86/entry/common.c:52 arch/x86/entry/common.c:83)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
WARNING: CPU: 1 PID: 11 at lib/ref_tracker.c:179 ref_tracker_dir_exit (lib/ref_tracker.c:179)
Modules linked in:
CPU: 1 UID: 0 PID: 11 Comm: kworker/u16:0 Not tainted 6.13.0-rc5-00147-g4c1224501e9d #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
Workqueue: netns cleanup_net
RIP: 0010:ref_tracker_dir_exit (lib/ref_tracker.c:179)
Code: 00 00 00 fc ff df 4d 8b 26 49 bd 00 01 00 00 00 00 ad de 4c 39 f5 0f 85 df 00 00 00 48 8b 74 24 08 48 89 df e8 a5 cc 12 02 90 <0f> 0b 90 48 8d 6b 44 be 04 00 00 00 48 89 ef e8 80 de 67 ff 48 89
RSP: 0018:ff11000007f3fb60 EFLAGS: 00010286
RAX: 00000000000020ef RBX: ff1100000d6481e0 RCX: 1ffffffff0e40d82
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8423ee3c
RBP: ff1100000d648230 R08: 0000000000000001 R09: fffffbfff0e395af
R10: 0000000000000001 R11: 0000000000000000 R12: ff1100000d648230
R13: dead000000000100 R14: ff1100000d648230 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ff1100006ce80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005620e1363990 CR3: 000000000eeb2002 CR4: 0000000000771ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
? __warn (kernel/panic.c:748)
? ref_tracker_dir_exit (lib/ref_tracker.c:179)
? report_bug (lib/bug.c:201 lib/bug.c:219)
? handle_bug (arch/x86/kernel/traps.c:285)
? exc_invalid_op (arch/x86/kernel/traps.c:309 (discriminator 1))
? asm_exc_invalid_op (./arch/x86/include/asm/idtentry.h:621)
? _raw_spin_unlock_irqrestore (./arch/x86/include/asm/irqflags.h:42 ./arch/x86/include/asm/irqflags.h:97 ./arch/x86/include/asm/irqflags.h:155 ./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194)
? ref_tracker_dir_exit (lib/ref_tracker.c:179)
? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:158)
? kfree (mm/slub.c:4613 mm/slub.c:4761)
net_free (net/core/net_namespace.c:476 net/core/net_namespace.c:467)
cleanup_net (net/cor
---truncated---
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
| December 29, 2024 | Reserved | Reserved by Linux |
| January 31, 2025 | Published | Published (CNA: Linux) |
| July 30, 2026 | RESCORED | RESCORED — CVE-2025-21677 (Linux). CVSS 7.8 → 5.5 (NVD). |
Affected
Affected products and packages — 2 rows
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
| Linux | Linux | — | 76c8764ef36a5d37ea2e551bda28ac7f028383ba | — |
| Linux | Linux | — | 6.10 | 6.12.11 |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2025-21677 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.