GHSA-2CVR-CMJ4-CJRX
Vulnerability from github – Published: 2026-07-19 12:30 – Updated: 2026-07-19 12:30In the Linux kernel, the following vulnerability has been resolved:
wifi: rtw88: usb: fix memory leaks on USB write failures
When rtw_usb_write_port() fails to submit a USB Request Block (URB) (e.g., due to device disconnect or ENOMEM), the completion callback is never executed.
Currently, the driver ignores the return value of rtw_usb_write_port() in rtw_usb_write_data() and rtw_usb_tx_agg_skb(). Because these functions rely on the completion callback to free the socket buffers (skbs) and the transaction control block (txcb), a submission failure results in: 1. A memory leak of the allocated skb in rtw_usb_write_data(). 2. A memory leak of the txcb structure and all aggregated skbs in rtw_usb_tx_agg_skb().
Fix this by checking the return value of rtw_usb_write_port(). If it fails, explicitly free the skb in rtw_usb_write_data(), and properly purge the tx_ack_queue and free the txcb in rtw_usb_tx_agg_skb().
The issue was discovered in practice during device disconnect/reconnect scenarios and memory pressure conditions. Tested by verifying normal TX operation continues after the fix without regressions.
{
"affected": [],
"aliases": [
"CVE-2026-63821"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-07-19T12:16:55Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: rtw88: usb: fix memory leaks on USB write failures\n\nWhen rtw_usb_write_port() fails to submit a USB Request Block (URB)\n(e.g., due to device disconnect or ENOMEM), the completion callback is\nnever executed.\n\nCurrently, the driver ignores the return value of rtw_usb_write_port()\nin rtw_usb_write_data() and rtw_usb_tx_agg_skb(). Because these\nfunctions rely on the completion callback to free the socket buffers\n(skbs) and the transaction control block (txcb), a submission failure\nresults in:\n1. A memory leak of the allocated skb in rtw_usb_write_data().\n2. A memory leak of the txcb structure and all aggregated skbs in\n rtw_usb_tx_agg_skb().\n\nFix this by checking the return value of rtw_usb_write_port(). If it\nfails, explicitly free the skb in rtw_usb_write_data(), and properly\npurge the tx_ack_queue and free the txcb in rtw_usb_tx_agg_skb().\n\nThe issue was discovered in practice during device disconnect/reconnect\nscenarios and memory pressure conditions. Tested by verifying normal TX\noperation continues after the fix without regressions.",
"id": "GHSA-2cvr-cmj4-cjrx",
"modified": "2026-07-19T12:30:24Z",
"published": "2026-07-19T12:30:23Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-63821"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/200d58c851b8f63f77a05570072dd20f79bc3681"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/2b2060c2075a72bc2de43ce5e1b9347d6c5e27bb"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/53fed4061a09755de99c89fdc7fae5b794da455f"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/6b964941bbfe6e0f18b1a5e008486dbb62df440a"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/8206d173d18ef5a077423119f4e9a93cb3a6f4eb"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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