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

Goal: 1000 CNY · Raised: 1000 CNY

100.0%
Buy Us a Coffee

CVE-2026-31617— usb: gadget: f_ncm: validate minimum block_len in ncm_unwrap_ntb()

EPSS 0.01% · P2
Get alerts for future matching vulnerabilitiesLog in to subscribe

I. Basic Information for CVE-2026-31617

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Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.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
usb: gadget: f_ncm: validate minimum block_len in ncm_unwrap_ntb()
Source: NVD (National Vulnerability Database)
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_ncm: validate minimum block_len in ncm_unwrap_ntb() The block_len read from the host-supplied NTB header is checked against ntb_max but has no lower bound. When block_len is smaller than opts->ndp_size, the bounds check of: ndp_index > (block_len - opts->ndp_size) will underflow producing a huge unsigned value that ndp_index can never exceed, defeating the check entirely. The same underflow occurs in the datagram index checks against block_len - opts->dpe_size. With those checks neutered, a malicious USB host can choose ndp_index and datagram offsets that point past the actual transfer, and the skb_put_data() copies adjacent kernel memory into the network skb. Fix this by rejecting block lengths that cannot hold at least the NTB header plus one NDP. This will make block_len - opts->ndp_size and block_len - opts->dpe_size both well-defined. Commit 8d2b1a1ec9f5 ("CDC-NCM: avoid overflow in sanity checking") fixed a related class of issues on the host side of NCM.
Source: NVD (National Vulnerability Database)
CVSS Information
N/A
Source: NVD (National Vulnerability Database)
Vulnerability Type
N/A
Source: NVD (National Vulnerability Database)
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ncm_unwrap_ntb中未验证最小block_len，可能导致整数下溢和内存泄漏。
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

VendorProductAffected VersionsCPESubscribe
LinuxLinux 2b74b0a04d3e9f9f08ff026e5663dce88ff94e52 ~ 0f156bb5334e588034ca68ac2ee92b23f66e56e7 -
LinuxLinux 5.9 -

II. Public POCs for CVE-2026-31617

#POC DescriptionSource LinkShenlong Link
AI-Generated POCPremium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-31617

请登录查看更多情报信息。

Same Patch Batch · Linux · 2026-04-24 · 138 CVEs total

CVE-2026-316499.8 CRITICALnet: stmmac: fix integer underflow in chain mode
CVE-2026-316079.8 CRITICALusbip: validate number_of_packets in usbip_pack_ret_submit()
CVE-2026-316089.8 CRITICALsmb: server: avoid double-free in smb_direct_free_sendmsg after smb_direct_flush_send_list
CVE-2026-316339.8 CRITICALrxrpc: Fix integer overflow in rxgk_verify_response()
CVE-2026-315369.8 CRITICALsmb: server: let send_done handle a completion without IB_SEND_SIGNALED
CVE-2026-316699.8 CRITICALmptcp: fix slab-use-after-free in __inet_lookup_established
CVE-2026-316689.8 CRITICALseg6: separate dst_cache for input and output paths in seg6 lwtunnel
CVE-2026-315899.8 CRITICALmm: call ->free_folio() directly in folio_unmap_invalidate()
CVE-2026-316099.8 CRITICALsmb: client: avoid double-free in smbd_free_send_io() after smbd_send_batch_flush()
CVE-2026-316579.8 CRITICALbatman-adv: hold claim backbone gateways by reference
CVE-2026-316599.8 CRITICALbatman-adv: reject oversized global TT response buffers
CVE-2026-316379.8 CRITICALrxrpc: reject undecryptable rxkad response tickets
CVE-2026-316369.1 CRITICALrxrpc: fix RESPONSE authenticator parser OOB read
CVE-2026-315708.8 HIGHcan: gw: fix OOB heap access in cgw_csum_crc8_rel()
CVE-2026-315588.8 HIGHLoongArch: KVM: Make kvm_get_vcpu_by_cpuid() more robust
CVE-2026-315538.8 HIGHKVM: arm64: Fix the descriptor address in __kvm_at_swap_desc()
CVE-2026-316298.8 HIGHnfc: llcp: add missing return after LLCP_CLOSED checks
CVE-2026-316228.8 HIGHNFC: digital: Bounds check NFC-A cascade depth in SDD response handler
CVE-2026-315888.8 HIGHKVM: x86: Use scratch field in MMIO fragment to hold small write values
CVE-2026-316118.6 HIGHksmbd: require 3 sub-authorities before reading sub_auth[2]

Showing top 20 of 138 CVEs. View all on vendor page → →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2026-31617

No comments yet

Leave a comment