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

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-31517— xfrm: iptfs: fix skb_put() panic on non-linear skb during reassembly

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基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于iptfs在重组期间对非线性skb调用skb_put，可能导致内核恐慌。

AI Predicted 7.5 Difficulty: Moderate EPSS 0.16% · P5

Affected Version Matrix 8

VendorProduct Version RangeStatus
Linux Linux 5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7< 33a7b36268933c75bdc355e5531951e0ea9f1951 affected
5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7< 7fdfe8f6efeb0e1200e22a903f2471539f54522b affected
5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7< 0b352f83cabfefdaafa806d6471f0eca117dc7d5 affected
6.14 affected
< 6.14 unaffected
6.18.21≤ 6.18.* unaffected
6.19.11≤ 6.19.* unaffected
7.0≤ * unaffected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-31517

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Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.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: iptfs: fix skb_put() panic on non-linear skb during reassembly
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: xfrm: iptfs: fix skb_put() panic on non-linear skb during reassembly In iptfs_reassem_cont(), IP-TFS attempts to append data to the new inner packet 'newskb' that is being reassembled. First a zero-copy approach is tried if it succeeds then newskb becomes non-linear. When a subsequent fragment in the same datagram does not meet the fast-path conditions, a memory copy is performed. It calls skb_put() to append the data and as newskb is non-linear it triggers SKB_LINEAR_ASSERT check. Oops: invalid opcode: 0000 [#1] SMP NOPTI [...] RIP: 0010:skb_put+0x3c/0x40 [...] Call Trace: <IRQ> iptfs_reassem_cont+0x1ab/0x5e0 [xfrm_iptfs] iptfs_input_ordered+0x2af/0x380 [xfrm_iptfs] iptfs_input+0x122/0x3e0 [xfrm_iptfs] xfrm_input+0x91e/0x1a50 xfrm4_esp_rcv+0x3a/0x110 ip_protocol_deliver_rcu+0x1d7/0x1f0 ip_local_deliver_finish+0xbe/0x1e0 __netif_receive_skb_core.constprop.0+0xb56/0x1120 __netif_receive_skb_list_core+0x133/0x2b0 netif_receive_skb_list_internal+0x1ff/0x3f0 napi_complete_done+0x81/0x220 virtnet_poll+0x9d6/0x116e [virtio_net] __napi_poll.constprop.0+0x2b/0x270 net_rx_action+0x162/0x360 handle_softirqs+0xdc/0x510 __irq_exit_rcu+0xe7/0x110 irq_exit_rcu+0xe/0x20 common_interrupt+0x85/0xa0 </IRQ> <TASK> Fix this by checking if the skb is non-linear. If it is, linearize it by calling skb_linearize(). As the initial allocation of newskb originally reserved enough tailroom for the entire reassembled packet we do not need to check if we have enough tailroom or extend it.
Source: CVE Program / CVE List V5
CVSS Information
N/A
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基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于iptfs在重组期间对非线性skb调用skb_put，可能导致内核恐慌。
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 5f2b6a9095743a6bf1f34c43c4fe78fa8bdf5ad7 ~ 33a7b36268933c75bdc355e5531951e0ea9f1951 -
Linux Linux 6.14 -

II. Public POCs for CVE-2026-31517

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

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-31517

请登录查看更多情报信息。

Same Patch Batch · Linux · 2026-04-22 · 100 CVEs total

CVE-2026-31463 9.8 CRITICAL iomap: fix invalid folio access when i_blkbits differs from I/O granularity
CVE-2026-31444 9.8 CRITICAL ksmbd: fix use-after-free and NULL deref in smb_grant_oplock()
CVE-2026-31501 9.8 CRITICAL net: ti: icssg-prueth: fix use-after-free of CPPI descriptor in RX path
CVE-2026-31436 9.8 CRITICAL dmaengine: idxd: fix possible wrong descriptor completion in llist_abort_desc()
CVE-2026-31478 9.8 CRITICAL ksmbd: replace hardcoded hdr2_len with offsetof() in smb2_calc_max_out_buf_len()
CVE-2026-31448 9.4 CRITICAL ext4: avoid infinite loops caused by residual data
CVE-2026-31450 8.8 HIGH ext4: publish jinode after initialization
CVE-2026-31432 8.8 HIGH ksmbd: fix OOB write in QUERY_INFO for compound requests
CVE-2026-31433 8.8 HIGH ksmbd: fix potencial OOB in get_file_all_info() for compound requests
CVE-2026-31435 8.8 HIGH netfs: Fix read abandonment during retry
CVE-2026-31476 8.2 HIGH ksmbd: do not expire session on binding failure
CVE-2026-31464 8.1 HIGH scsi: ibmvfc: Fix OOB access in ibmvfc_discover_targets_done()
CVE-2026-31513 8.1 HIGH Bluetooth: L2CAP: Fix stack-out-of-bounds read in l2cap_ecred_conn_req
CVE-2026-31446 7.8 HIGH ext4: fix use-after-free in update_super_work when racing with umount
CVE-2026-31449 7.8 HIGH ext4: validate p_idx bounds in ext4_ext_correct_indexes
CVE-2026-31502 7.8 HIGH team: fix header_ops type confusion with non-Ethernet ports
CVE-2026-31431 7.8 HIGH crypto: algif_aead - Revert to operating out-of-place
CVE-2026-31488 7.8 HIGH drm/amd/display: Do not skip unrelated mode changes in DSC validation
CVE-2026-31490 7.8 HIGH drm/xe/pf: Fix use-after-free in migration restore
CVE-2026-31454 7.8 HIGH xfs: save ailp before dropping the AIL lock in push callbacks

Showing top 20 of 100 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2026-31517

No comments yet

Leave a comment