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

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-74705— udp: fix potential use-after-free in tunnel segmentation

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 4.6版本存在安全漏洞，该漏洞源于__skb_udp_tunnel_segment函数在隧道分段中过早获取UDP头，当pull重新分配skb->head时，已保存的UDP头指针不再有效，可能导致释放后重用。

CVSS 10.0 · Critical EPSS 0.50% · P41

Possible ATT&CK Techniques 1 AI

T1068 · Exploitation for Privilege Escalation

Affected Version Matrix 18

VendorProduct Version RangeStatus
Linux Linux dbef491ebe7f3a4fb1b9111878b86a426fd540b7< 6a733a38b983d8c2e222f13968209010cf44de87 affected
dbef491ebe7f3a4fb1b9111878b86a426fd540b7< 19d89b13a43640b2da2f277ee462d919d988cb6f affected
dbef491ebe7f3a4fb1b9111878b86a426fd540b7< b3df61bb745eb5201eac22679a2839d4ccbf3442 affected
dbef491ebe7f3a4fb1b9111878b86a426fd540b7< 1ae134c012e10384cdac420b5cc6e0615cde0b55 affected
dbef491ebe7f3a4fb1b9111878b86a426fd540b7< 5161e67c561c4f28a5d9335a6e859b02511de92b affected
dbef491ebe7f3a4fb1b9111878b86a426fd540b7< 64d322c288577793eedd352b96ef75234ed380fe affected
dbef491ebe7f3a4fb1b9111878b86a426fd540b7< 588d4a6795d99d080f74ef0b5f391ea8c453ae5d affected
dbef491ebe7f3a4fb1b9111878b86a426fd540b7< d0f86fb36eb260abd10007b62c9dcc1028e03e61 affected
… +10 more rows
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-74705

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Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.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
udp: fix potential use-after-free in tunnel segmentation
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: udp: fix potential use-after-free in tunnel segmentation __skb_udp_tunnel_segment() gets the UDP header before ensuring the tunnel header is in the skb head. If the pull reallocates skb->head, the saved UDP header pointer is no longer valid. Get the UDP header after the pull to avoid a potential use-after-free.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/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 4.6版本存在安全漏洞，该漏洞源于__skb_udp_tunnel_segment函数在隧道分段中过早获取UDP头，当pull重新分配skb->head时，已保存的UDP头指针不再有效，可能导致释放后重用。
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 dbef491ebe7f3a4fb1b9111878b86a426fd540b7 ~ 6a733a38b983d8c2e222f13968209010cf44de87 -
Linux Linux 4.6 -

II. Public POCs for CVE-2026-74705

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

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-74705

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-74705 (6)

Other References for CVE-2026-74705 (1)

Same Patch Batch · Linux · 2026-08-22 · 149 CVEs total

CVE-2026-74612 10.0 CRITICAL veth: fix skb length accounting after XDP frag adjustment
CVE-2026-74611 9.8 CRITICAL tls: rx: restore msg_iter before TLS 1.3 optimistic retry
CVE-2026-74669 9.8 CRITICAL ipvs: clear IPv4 options after rebasing tunnel ICMP errors
CVE-2026-74608 9.8 CRITICAL smb: client: Fix use-after-free in cifs_try_adding_channels()
CVE-2026-74723 9.8 CRITICAL btrfs: lzo: reject inline extents without valid headers
CVE-2026-74727 9.8 CRITICAL ovpn: skip rehash for peers already removed from by_id
CVE-2026-74688 9.8 CRITICAL sctp: clear control chunk transport if it is being removed
CVE-2026-74628 9.8 CRITICAL net/x25: fix use-after-free of the socket by its timers
CVE-2026-74662 9.8 CRITICAL inet: frags: publish queues before arming timer
CVE-2026-74597 9.8 CRITICAL ip6_tunnel: clear skb2->cb[] in ip6ip6_err()
CVE-2026-74617 9.8 CRITICAL dibs: initialise dibs->lock in dibs_dev_alloc()
CVE-2026-74730 9.8 CRITICAL NFS: Pin the 'struct nfs_server' during a FREE_STATEID call
CVE-2026-74616 9.8 CRITICAL xdp: reject clones that overrun skb_shared_info tailroom
CVE-2026-74586 9.8 CRITICAL sctp: clear new_transport when removing a peer
CVE-2026-74587 9.8 CRITICAL sctp: fix use-after-free of cached ASCONF chunk
CVE-2026-74588 9.8 CRITICAL sctp: keep chunk->transport in step with the list it is queued on
CVE-2026-74591 9.8 CRITICAL mm/filemap: __filemap_add_folio() restore index before retrying
CVE-2026-74712 9.3 CRITICAL vdpa/mlx5: Fix buffer length in create_direct_keys()
CVE-2026-74665 9.1 CRITICAL net: fix skb length accounting after generic XDP frag adjustment
CVE-2026-74655 8.8 HIGH serial: qcom-geni: fix TX DMA buffer flush

Showing top 20 of 149 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2026-74705

No comments yet

Leave a comment