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GHSA-2CVR-CMJ4-CJRX

Vulnerability from github – Published: 2026-07-19 12:30 – Updated: 2026-07-19 12:30

Details

In 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.

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{
  "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": []
}

CVE-2026-63821 (GCVE-0-2026-63821)

Vulnerability from cvelistv5 – Published: 2026-07-19 12:02 – Updated: 2026-08-17 04:51

Title

wifi: rtw88: usb: fix memory leaks on USB write failures

Summary

In 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.

Severity

No CVSS data available.

Assigner

Linux mitre root

References

5 references

URL	Tags
https://git.kernel.org/stable/c/2b2060c2075a72bc2…
https://git.kernel.org/stable/c/53fed4061a09755de…
https://git.kernel.org/stable/c/200d58c851b8f63f7…
https://git.kernel.org/stable/c/8206d173d18ef5a07…
https://git.kernel.org/stable/c/6b964941bbfe6e0f1…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: a82dfd33d1237f6c0fb8a7077022189d1fc7ec98 , < 2b2060c2075a72bc2de43ce5e1b9347d6c5e27bb (git) Affected: a82dfd33d1237f6c0fb8a7077022189d1fc7ec98 , < 53fed4061a09755de99c89fdc7fae5b794da455f (git) Affected: a82dfd33d1237f6c0fb8a7077022189d1fc7ec98 , < 200d58c851b8f63f77a05570072dd20f79bc3681 (git) Affected: a82dfd33d1237f6c0fb8a7077022189d1fc7ec98 , < 8206d173d18ef5a077423119f4e9a93cb3a6f4eb (git) Affected: a82dfd33d1237f6c0fb8a7077022189d1fc7ec98 , < 6b964941bbfe6e0f18b1a5e008486dbb62df440a (git)
Linux	Linux	Affected: 6.2 Unaffected: 0 , < 6.2 (semver) Unaffected: 6.6.144 , ≤ 6.6.* (semver) Unaffected: 6.12.95 , ≤ 6.12.* (semver) Unaffected: 6.18.38 , ≤ 6.18.* (semver) Unaffected: 7.1.3 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

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JSON

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      "cpeApplicability": [
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}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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