ghsa-whrv-v478-pw4q
Vulnerability from github
Published
2025-09-05 18:31
Modified
2025-09-05 18:31
Details

In the Linux kernel, the following vulnerability has been resolved:

parisc: Revise gateway LWS calls to probe user read access

We use load and stbys,e instructions to trigger memory reference interruptions without writing to memory. Because of the way read access support is implemented, read access interruptions are only triggered at privilege levels 2 and 3. The kernel and gateway page execute at privilege level 0, so this code never triggers a read access interruption. Thus, it is currently possible for user code to execute a LWS compare and swap operation at an address that is read protected at privilege level 3 (PRIV_USER).

Fix this by probing read access rights at privilege level 3 and branching to lws_fault if access isn't allowed.

Show details on source website

To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2025-39715"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-09-05T18:15:48Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nparisc: Revise gateway LWS calls to probe user read access\n\nWe use load and stbys,e instructions to trigger memory reference\ninterruptions without writing to memory. Because of the way read\naccess support is implemented, read access interruptions are only\ntriggered at privilege levels 2 and 3. The kernel and gateway\npage execute at privilege level 0, so this code never triggers\na read access interruption. Thus, it is currently possible for\nuser code to execute a LWS compare and swap operation at an\naddress that is read protected at privilege level 3 (PRIV_USER).\n\nFix this by probing read access rights at privilege level 3 and\nbranching to lws_fault if access isn\u0027t allowed.",
  "id": "GHSA-whrv-v478-pw4q",
  "modified": "2025-09-05T18:31:27Z",
  "published": "2025-09-05T18:31:27Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-39715"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8bccf47adbf658293528e86960e6d6f736b1c9f7"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9b6af875baba9c4679b55f4561e201485451305f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/bc0a24c24ceebabb5ba65900e332233d79e625e6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e8b496c52aa0c6572d88db7cab85aeea6f9c194d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f6334f4ae9a4e962ba74b026e1d965dfdf8cbef8"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.