Linux Kernel up to 7.0-rc4 net cdc_ncm_rx_verify_ndp16 out-of-bounds

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.6$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in Linux Kernel up to 6.6.129/6.12.77/6.18.19/6.19.9/7.0-rc4. This impacts the function cdc_ncm_rx_verify_ndp16 of the component net. The manipulation leads to out-of-bounds. This vulnerability is listed as CVE-2026-23448. There is no available exploit. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Linux Kernel up to 6.6.129/6.12.77/6.18.19/6.19.9/7.0-rc4. This issue affects the function cdc_ncm_rx_verify_ndp16 of the component net. The manipulation with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: net: usb: cdc_ncm: add ndpoffset to NDP16 nframes bounds check cdc_ncm_rx_verify_ndp16() validates that the NDP header and its DPE entries fit within the skb. The first check correctly accounts for ndpoffset: if ((ndpoffset + sizeof(struct usb_cdc_ncm_ndp16)) > skb_in->len) but the second check omits it: if ((sizeof(struct usb_cdc_ncm_ndp16) + ret * (sizeof(struct usb_cdc_ncm_dpe16))) > skb_in->len) This validates the DPE array size against the total skb length as if the NDP were at offset 0, rather than at ndpoffset. When the NDP is placed near the end of the NTB (large wNdpIndex), the DPE entries can extend past the skb data buffer even though the check passes. cdc_ncm_rx_fixup() then reads out-of-bounds memory when iterating the DPE array. Add ndpoffset to the nframes bounds check and use struct_size_t() to express the NDP-plus-DPE-array size more clearly.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2026-23448 since 01/13/2026. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 321690 (SUSE SLES12 Security Update : kernel (SUSE-SU-2026:2450-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.6.130, 6.12.78, 6.18.20, 6.19.10 or 7.0-rc5 eliminates this vulnerability. Applying the patch f1c7701d3ac91b62d672c13690cf295821f0d5c3/789204f980730258c983102c027c375238009c80/403f94ddcb36c552fbef51dea735b131e3dcde8b/dce9dda0e3707e887977db44407989e9ead26611/2aa8a4fa8d5b7d0e1ebcec100e1a4d80a1f4b21a is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (321690) and CERT Bund (WID-SEC-2026-0985). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • Open Source Linux Kernel
  • RESF Rocky Linux
  • Microsoft Azure Linux

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.6

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Nessus ID: 321690
Nessus Name: SUSE SLES12 Security Update : kernel (SUSE-SU-2026:2450-1)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.6.130/6.12.78/6.18.20/6.19.10/7.0-rc5
Patch: f1c7701d3ac91b62d672c13690cf295821f0d5c3/789204f980730258c983102c027c375238009c80/403f94ddcb36c552fbef51dea735b131e3dcde8b/dce9dda0e3707e887977db44407989e9ead26611/2aa8a4fa8d5b7d0e1ebcec100e1a4d80a1f4b21a

Timelineinfo

01/13/2026 CVE reserved
04/03/2026 +79 days Advisory disclosed
04/03/2026 +0 days VulDB entry created
06/25/2026 +83 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-23448 (🔒)
GCVE (CVE): GCVE-0-2026-23448
GCVE (VulDB): GCVE-100-355133
CERT Bund: WID-SEC-2026-0985 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 04/03/2026 18:08
Updated: 06/25/2026 08:08
Changes: 04/03/2026 18:08 (59), 05/11/2026 19:48 (7), 05/21/2026 03:04 (11), 06/21/2026 07:48 (2), 06/25/2026 08:08 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Discussion

No comments yet. Languages: en.

Please log in to comment.

Do you know our Splunk app?

Download it now for free!