Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-68420— xfrm: reject optional IPTFS templates in outbound policies

Quick assessment

Affected
Linux Linux
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Linux kernel是美国Linux基金会开源的一个操作系统内核。 Linux kernel存在安全漏洞，该漏洞源于xfrm模块未正确拒绝出站策略中的可选IPTFS模板，可能导致栈越界读取。

CVSS 7.1 · High EPSS 0.11% · P1

Possible ATT&CK Techniques 1 AI

T1190 · Exploit Public-Facing Application

Affected Version Matrix 8

VendorProduct Version RangeStatus
Linux Linux d1716d5a44c37e5743bf6ea4e5cdbdab37727f27< d7fc6f351c478586980a521d63b0214d9c055e78 affected
d1716d5a44c37e5743bf6ea4e5cdbdab37727f27< 9333f4b6f44858fc98eb12bf26b8d2959eb975d5 affected
d1716d5a44c37e5743bf6ea4e5cdbdab37727f27< ea528f18231ec0f33317be57f8866913b19aba6e affected
6.14 affected
< 6.14 unaffected
6.18.42≤ 6.18.* unaffected
7.1.6≤ 7.1.* unaffected
7.2≤ * unaffected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-68420

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
xfrm: reject optional IPTFS templates in outbound policies
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: xfrm: reject optional IPTFS templates in outbound policies syzbot reported a stack-out-of-bounds read in xfrm_state_find() which flows from xfrm_tmpl_resolve_one(). Commit 3d776e31c841 ("xfrm: Reject optional tunnel/BEET mode templates in outbound policies") disallowed optional tunnel and BEET in outbound policies to prevent this. Later when IPTFS added, it was not covered by that fix and can still trigger the out-of-bounds read; Extend the check to disallow optional IPTFS in outbound policies as well. IPTFS should be identical to tunnel mode. IN and FWD policies are not affected: xfrm_tmpl_resolve_one() is only reachable via the outbound path. Reproducer, before: ip link add dummy0 type dummy ip link set dummy0 up ip addr add 10.1.1.1/24 dev dummy0 ip xfrm policy add src 10.1.1.1/32 dst 10.1.1.2/32 dir out tmpl src fc00::dead:1 dst fc00::dead:2 proto esp reqid 1 mode iptfs level use tmpl src fc00::dead:1 dst fc00::dead:2 proto esp reqid 2 mode transport ping -W 1 -c 1 10.1.1.2 PING 10.1.1.2 (10.1.1.2) 56(84) bytes of data. [ 64.168420] ================================================================== [ 64.169977] BUG: KASAN: stack-out-of-bounds in __xfrm6_addr_hash+0x11e/0x170 [ 64.169977] Read of size 4 at addr ffff88800e1ffd20 by task ping/2844 [ 64.169977] CPU: 2 UID: 0 PID: 2844 Comm: ping Not tainted 7.1.0-rc7-00180-geb23b588430a #98 PREEMPT(full) [ 64.169977] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 64.169977] Call Trace: [ 64.169977] <TASK> [ 64.169977] dump_stack_lvl+0x47/0x70 [ 64.169977] ? __xfrm6_addr_hash+0x11e/0x170 [ 64.169977] print_report+0x152/0x4b0 [ 64.169977] ? ksys_mmap_pgoff+0x6d/0xa0 [ 64.169977] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 64.169977] ? rcu_read_unlock_sched+0xa/0x20 [ 64.169977] ? __virt_addr_valid+0x21b/0x230 [ 64.169977] ? __xfrm6_addr_hash+0x11e/0x170 [ 64.169977] kasan_report+0xa8/0xd0 [ 64.169977] ? __xfrm6_addr_hash+0x11e/0x170 [ 64.169977] __xfrm6_addr_hash+0x11e/0x170 [ 64.169977] __xfrm_dst_hash+0x24/0xc0 [ 64.169977] xfrm_state_find+0xa2d/0x2f90 [ 64.169977] ? __pfx_xfrm_state_find+0x10/0x10 [ 64.169977] ? __pfx_ftrace_graph_ret_addr+0x10/0x10 [ 64.169977] ? __pfx_ftrace_graph_ret_addr+0x10/0x10 [ 64.169977] xfrm_tmpl_resolve_one+0x210/0x570 [ 64.169977] ? __pfx_xfrm_tmpl_resolve_one+0x10/0x10 [ 64.169977] ? __pfx_stack_trace_consume_entry+0x10/0x10 [ 64.169977] ? kernel_text_address+0x5b/0x80 [ 64.169977] ? __kernel_text_address+0xe/0x30 [ 64.169977] ? unwind_get_return_address+0x5e/0x90 [ 64.169977] ? arch_stack_walk+0x8c/0xe0 [ 64.169977] xfrm_tmpl_resolve+0x130/0x200 [ 64.169977] ? __pfx_xfrm_tmpl_resolve+0x10/0x10 [ 64.169977] ? __pfx_xfrm_policy_inexact_lookup_rcu+0x10/0x10 [ 64.169977] ? __refcount_add_not_zero.constprop.0+0xb2/0x110 [ 64.169977] ? __pfx___refcount_add_not_zero.constprop.0+0x10/0x10 [ 64.169977] xfrm_resolve_and_create_bundle+0xd5/0x310 [ 64.169977] ? __pfx_xfrm_resolve_and_create_bundle+0x10/0x10 [ 64.169977] ? __pfx_xfrm_policy_lookup_bytype+0x10/0x10 [ 64.169977] ? __pfx_xfrm_policy_lookup_bytype+0x10/0x10 [ 64.169977] xfrm_lookup_with_ifid+0x3d8/0xb80 [ 64.169977] ? __pfx_xfrm_lookup_with_ifid+0x10/0x10 [ 64.169977] ? ip_route_output_key_hash+0xc6/0x110 [ 64.169977] ? kasan_save_track+0x10/0x30 [ 64.169977] xfrm_lookup_route+0x18/0xe0 [ 64.169977] ip4_datagram_release_cb+0x4c9/0x530 [ 64.169977] ? __pfx_ip4_datagram_release_cb+0x10/0x10 [ 64.169977] ? do_raw_spin_lock+0x71/0xc0 [ 64.169977] ? __pfx_do_raw_spin_lock+0x10/0x10 [ 64.169977] release_sock+0xb0/0x170 [ 64.169977] udp_connect+0x43/0x50 [ 64.169977] __sys_connect+0xa6/0x100 [ 64.169977] ? alloc_fd+0x2e9/0x300 [ 64.169977] ? __pfx___sys_connect+0x10/0x10 [ 64.169977] ? preempt_latency ---truncated---
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5
Vulnerability Title
Linux kernel 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Linux kernel是美国Linux基金会开源的一个操作系统内核。 Linux kernel存在安全漏洞，该漏洞源于xfrm模块未正确拒绝出站策略中的可选IPTFS模板，可能导致栈越界读取。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
Linux Linux d1716d5a44c37e5743bf6ea4e5cdbdab37727f27 ~ d7fc6f351c478586980a521d63b0214d9c055e78 -
Linux Linux 6.14 -

II. Public POCs for CVE-2026-68420

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-68420

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-68420 (2)

Same Patch Batch · Linux · 2026-08-10 · 344 CVEs total

CVE-2026-68302 9.8 CRITICAL amt: re-read skb header pointers after every pull
CVE-2026-68388 9.8 CRITICAL smb/client: handle overlapping allocated ranges in fallocate
CVE-2026-68161 9.8 CRITICAL sctp: close UDP tunnel sockets during netns teardown
CVE-2026-68385 9.8 CRITICAL s390/checksum: Fix csum_partial() without vector facility
CVE-2026-68381 9.8 CRITICAL ksmbd: pin conn during async oplock break notification
CVE-2026-68160 9.8 CRITICAL ceph: fix pre-auth out-of-bounds read on snaptrace in ceph_handle_caps()
CVE-2026-68123 9.8 CRITICAL openvswitch: fix GSO userspace truncation underflow
CVE-2026-68300 9.8 CRITICAL sctp: auth: verify auth requirement when auth_chunk is NULL
CVE-2026-68127 9.8 CRITICAL ila: reload IPv6 header after pskb_may_pull in checksum adjust
CVE-2026-68117 9.8 CRITICAL tipc: clear sock->sk on the failed-insert path in tipc_sk_create()
CVE-2026-68159 9.8 CRITICAL libceph: bound pg_{temp,upmap,upmap_items} length to CEPH_PG_MAX_SIZE
CVE-2026-68158 9.8 CRITICAL libceph: Fix multiplication overflow in decode_new_up_state_weight()
CVE-2026-68136 9.8 CRITICAL net: gro: fix double aggregation of flush-marked skbs
CVE-2026-68426 9.8 CRITICAL xfrm: fix stale skb->prev after async crypto steals a GSO segment
CVE-2026-68170 9.8 CRITICAL mptcp: fix stale skb->sk reference on subflow close
CVE-2026-68144 9.8 CRITICAL phonet: pep: fix use-after-free in pep_get_sb()
CVE-2026-68137 9.8 CRITICAL net/x25: fix use-after-free in x25_kill_by_neigh()
CVE-2026-68156 9.8 CRITICAL libceph: refresh auth->authorizer_buf{,_len} after authorizer update
CVE-2026-68154 9.8 CRITICAL libceph: reject zero bucket types in crush_decode
CVE-2026-68124 9.6 CRITICAL mctp: serial: handle zero-length frames to prevent rx buffer overflow

Showing top 20 of 344 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2026-68420

No comments yet

Leave a comment