Linux Kernel up to 6.13.6 atm drivers/usb/core/urb.c cxacru_bind privilege escalation

CVSS Meta Temp Score
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CTI Interest Score
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4.9$0-$5k0.00

Summaryinfo

A vulnerability described as problematic has been identified in Linux Kernel up to 6.13.6. This impacts the function cxacru_bind of the file drivers/usb/core/urb.c of the component atm. Executing a manipulation can lead to an unknown weakness. This vulnerability appears as CVE-2025-21916. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as problematic was found in Linux Kernel up to 6.13.6. This vulnerability affects the function cxacru_bind of the file drivers/usb/core/urb.c of the component atm. The impact remains unknown. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: usb: atm: cxacru: fix a flaw in existing endpoint checks Syzbot once again identified a flaw in usb endpoint checking, see [1]. This time the issue stems from a commit authored by me (2eabb655a968 ("usb: atm: cxacru: fix endpoint checking in cxacru_bind()")). While using usb_find_common_endpoints() may usually be enough to discard devices with wrong endpoints, in this case one needs more than just finding and identifying the sufficient number of endpoints of correct types - one needs to check the endpoint's address as well. Since cxacru_bind() fills URBs with CXACRU_EP_CMD address in mind, switch the endpoint verification approach to usb_check_XXX_endpoints() instead to fix incomplete ep testing. [1] Syzbot report: usb 5-1: BOGUS urb xfer, pipe 3 != type 1 WARNING: CPU: 0 PID: 1378 at drivers/usb/core/urb.c:504 usb_submit_urb+0xc4e/0x18c0 drivers/usb/core/urb.c:503 ... RIP: 0010:usb_submit_urb+0xc4e/0x18c0 drivers/usb/core/urb.c:503 ... Call Trace: <TASK> cxacru_cm+0x3c8/0xe50 drivers/usb/atm/cxacru.c:649 cxacru_card_status drivers/usb/atm/cxacru.c:760 [inline] cxacru_bind+0xcf9/0x1150 drivers/usb/atm/cxacru.c:1223 usbatm_usb_probe+0x314/0x1d30 drivers/usb/atm/usbatm.c:1058 cxacru_usb_probe+0x184/0x220 drivers/usb/atm/cxacru.c:1377 usb_probe_interface+0x641/0xbb0 drivers/usb/core/driver.c:396 really_probe+0x2b9/0xad0 drivers/base/dd.c:658 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800 driver_probe_device+0x50/0x430 drivers/base/dd.c:830 ...

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2025-21916 since 12/29/2024. The exploitation appears to be difficult. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 234309 (Debian dsa-5900 : affs-modules-6.1.0-28-4kc-malta-di - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.4.291, 5.10.235, 5.15.179, 6.1.131, 6.6.83, 6.12.19 or 6.13.7 eliminates this vulnerability. Applying the patch dcd592ab9dd8a2bfc36e75583b9006db2a77ec24/319529e0356bd904528c64647725a2272d297c83/bf4409f84023b52b5e9b36c0a071a121eee42138/197e78076c5ecd895f109158c4ea2954b9919af6/a0475a885d69849b1ade38add6d64338dfa83a8f/cfc295f7cccf66cbd5123416bcf1bee2e1bd37de/903b80c21458bb1e34c3a78c5fdc553821e357f8/c90aad369899a607cfbc002bebeafd51e31900cd 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 (234309) and CERT Bund (WID-SEC-2025-0683). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • RESF Rocky Linux
  • Dell Avamar
  • Open Source Linux Kernel
  • SolarWinds Security Event Manager
  • Dell NetWorker
  • Dell Secure Connect Gateway
  • IBM Security Verify Access

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.0
VulDB Meta Temp Score: 4.9

VulDB Base Score: 4.6
VulDB Temp Score: 4.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Privilege escalation
CWE: Unknown
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 234309
Nessus Name: Debian dsa-5900 : affs-modules-6.1.0-28-4kc-malta-di - security update

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 5.4.291/5.10.235/5.15.179/6.1.131/6.6.83/6.12.19/6.13.7
Patch: dcd592ab9dd8a2bfc36e75583b9006db2a77ec24/319529e0356bd904528c64647725a2272d297c83/bf4409f84023b52b5e9b36c0a071a121eee42138/197e78076c5ecd895f109158c4ea2954b9919af6/a0475a885d69849b1ade38add6d64338dfa83a8f/cfc295f7cccf66cbd5123416bcf1bee2e1bd37de/903b80c21458bb1e34c3a78c5fdc553821e357f8/c90aad369899a607cfbc002bebeafd51e31900cd

Timelineinfo

12/29/2024 🔍
04/01/2025 +92 days 🔍
04/01/2025 +0 days 🔍
02/01/2026 +306 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-21916 (🔍)
GCVE (CVE): GCVE-0-2025-21916
GCVE (VulDB): GCVE-100-302608
CERT Bund: WID-SEC-2025-0683 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 04/01/2025 18:57
Updated: 02/01/2026 05:13
Changes: 04/01/2025 18:57 (58), 04/14/2025 13:56 (2), 07/20/2025 00:15 (7), 07/21/2025 19:19 (1), 10/26/2025 19:41 (1), 10/31/2025 21:30 (13), 02/01/2026 05:13 (1)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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