Answer in brief
CVE-2024-26996 records a Unknown severity vulnerability in usb: gadget: f_ncm: Fix UAF ncm object at re-bind after usb ep transport error. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
Answer in brief
CVE-2024-26996 records a Unknown severity vulnerability in usb: gadget: f_ncm: Fix UAF ncm object at re-bind after usb ep transport error. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=6b4012a2e4d4702f8fb0ee1db1c0f0b17ab7d41b <7f67c2020cb08499c400abf0fc32c65e4d9a09ca || >=6b4012a2e4d4702f8fb0ee1db1c0f0b17ab7d41b <0588bbbd718a8130b98c54518f1e0b569ce60a93 || >=6b4012a2e4d4702f8fb0ee1db1c0f0b17ab7d41b <f356fd0cbd9c9cbd0854657a80d1608d0d732db3 || >=6b4012a2e4d4702f8fb0ee1db1c0f0b17ab7d41b <7250326cbb1f4f90391ac511a126b936cefb5bb7 || >=6b4012a2e4d4702f8fb0ee1db1c0f0b17ab7d41b <6334b8e4553cc69f51e383c9de545082213d785e | 7f67c2020cb08499c400abf0fc32c65e4d9a09ca, 0588bbbd718a8130b98c54518f1e0b569ce60a93, f356fd0cbd9c9cbd0854657a80d1608d0d732db3, 7250326cbb1f4f90391ac511a126b936cefb5bb7, 6334b8e4553cc69f51e383c9de545082213d785e |
| Linux/Linuxgeneric | 4.4 | Not reported |
Published upstream
May 1, 2024
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_ncm: Fix UAF ncm object at re-bind after usb ep transport error When ncm function is working and then stop usb0 interface for link down, eth_stop() is called. At this piont, accidentally if usb transport error should happen in usb_ep_enable(), 'in_ep' and/or 'out_ep' may not be enabled. After that, ncm_disable() is called to disable for ncm unbind but gether_disconnect() is never called since 'in_ep' is not enabled. As the result, ncm object is released in ncm unbind but 'dev->port_usb' associated to 'ncm->port' is not NULL. And when ncm bind again to recover netdev, ncm object is reallocated but usb0 interface is already associated to previous released ncm object. Therefore, once usb0 interface is up and eth_start_xmit() is called, released ncm object is dereferrenced and it might cause use-after-free memory. [function unlink via configfs] usb0: eth_stop dev->port_usb=ffffff9b179c3200 --> error happens in usb_ep_enable(). NCM: ncm_disable: ncm=ffffff9b179c3200 --> no gether_disconnect() since ncm->port.in_ep->enabled is false. NCM: ncm_unbind: ncm unbind ncm=ffffff9b179c3200 NCM: ncm_free: ncm free ncm=ffffff9b179c3200 <-- released ncm [function link via configfs] NCM: ncm_alloc: ncm alloc ncm=ffffff9ac4f8a000 NCM: ncm_bind: ncm bind ncm=ffffff9ac4f8a000 NCM: ncm_set_alt: ncm=ffffff9ac4f8a000 alt=0 usb0: eth_open dev->port_usb=ffffff9b179c3200 <-- previous released ncm usb0: eth_start dev->port_usb=ffffff9b179c3200 <-- eth_start_xmit() --> dev->wrap() Unable to handle kernel paging request at virtual address dead00000000014f This patch addresses the issue by checking if 'ncm->netdev' is not NULL at ncm_disable() to call gether_disconnect() to deassociate 'dev->port_usb'. It's more reasonable to check 'ncm->netdev' to call gether_connect/disconnect rather than check 'ncm->port.in_ep->enabled' since it might not be enabled but the gether connection might be established.
Quoted source text, attributed separately from HOL analysis.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=6b4012a2e4d4702f8fb0ee1db1c0f0b17ab7d41b <7f67c2020cb08499c400abf0fc32c65e4d9a09ca || >=6b4012a2e4d4702f8fb0ee1db1c0f0b17ab7d41b <0588bbbd718a8130b98c54518f1e0b569ce60a93 || >=6b4012a2e4d4702f8fb0ee1db1c0f0b17ab7d41b <f356fd0cbd9c9cbd0854657a80d1608d0d732db3 || >=6b4012a2e4d4702f8fb0ee1db1c0f0b17ab7d41b <7250326cbb1f4f90391ac511a126b936cefb5bb7 || >=6b4012a2e4d4702f8fb0ee1db1c0f0b17ab7d41b <6334b8e4553cc69f51e383c9de545082213d785e | 7f67c2020cb08499c400abf0fc32c65e4d9a09ca, 0588bbbd718a8130b98c54518f1e0b569ce60a93, f356fd0cbd9c9cbd0854657a80d1608d0d732db3, 7250326cbb1f4f90391ac511a126b936cefb5bb7, 6334b8e4553cc69f51e383c9de545082213d785e |
| Linux/Linuxgeneric | 4.4 | Not reported |
Published upstream
May 1, 2024
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_ncm: Fix UAF ncm object at re-bind after usb ep transport error When ncm function is working and then stop usb0 interface for link down, eth_stop() is called. At this piont, accidentally if usb transport error should happen in usb_ep_enable(), 'in_ep' and/or 'out_ep' may not be enabled. After that, ncm_disable() is called to disable for ncm unbind but gether_disconnect() is never called since 'in_ep' is not enabled. As the result, ncm object is released in ncm unbind but 'dev->port_usb' associated to 'ncm->port' is not NULL. And when ncm bind again to recover netdev, ncm object is reallocated but usb0 interface is already associated to previous released ncm object. Therefore, once usb0 interface is up and eth_start_xmit() is called, released ncm object is dereferrenced and it might cause use-after-free memory. [function unlink via configfs] usb0: eth_stop dev->port_usb=ffffff9b179c3200 --> error happens in usb_ep_enable(). NCM: ncm_disable: ncm=ffffff9b179c3200 --> no gether_disconnect() since ncm->port.in_ep->enabled is false. NCM: ncm_unbind: ncm unbind ncm=ffffff9b179c3200 NCM: ncm_free: ncm free ncm=ffffff9b179c3200 <-- released ncm [function link via configfs] NCM: ncm_alloc: ncm alloc ncm=ffffff9ac4f8a000 NCM: ncm_bind: ncm bind ncm=ffffff9ac4f8a000 NCM: ncm_set_alt: ncm=ffffff9ac4f8a000 alt=0 usb0: eth_open dev->port_usb=ffffff9b179c3200 <-- previous released ncm usb0: eth_start dev->port_usb=ffffff9b179c3200 <-- eth_start_xmit() --> dev->wrap() Unable to handle kernel paging request at virtual address dead00000000014f This patch addresses the issue by checking if 'ncm->netdev' is not NULL at ncm_disable() to call gether_disconnect() to deassociate 'dev->port_usb'. It's more reasonable to check 'ncm->netdev' to call gether_connect/disconnect rather than check 'ncm->port.in_ep->enabled' since it might not be enabled but the gether connection might be established.
Quoted source text, attributed separately from HOL analysis.