GHSA-X7FX-9652-J55V
Vulnerability from github – Published: 2026-09-11 21:31 – Updated: 2026-09-13 09:32In the Linux kernel, the following vulnerability has been resolved:
cxl/features: bound fwctl command payload to the input buffer
fwctl_cmd_rpc() copies cmd->in_len bytes into inbuf = kvzalloc(cmd->in_len) and passes inbuf and in_len to ->fw_rpc(). The CXL callback cxlctl_fw_rpc() ignores in_len and never checks the user-controlled op_size against it.
cxlctl_set_feature() bounds op_size only from below (op_size <= sizeof(feat_in->hdr)) and then reads op_size - sizeof(hdr) bytes from feat_in->feat_data via cxl_set_feature(). With a small in_len and a large op_size the first memcpy() already reads past the kvzalloc(in_len) buffer; the out-of-bounds bytes are placed in the mailbox payload and sent to the device, and a large enough op_size can walk into unmapped memory and oops the kernel. The Get paths pin op_size to a fixed size but likewise read the input struct without checking in_len.
Reject, at the single dispatch point, any request whose fixed header plus op_size does not fit in the copied-in buffer. The lower-bound test guards the subtraction and ensures op_size was copied in before it is read.
{
"affected": [],
"aliases": [
"CVE-2026-89571"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-09-11T20:19:41Z",
"severity": "HIGH"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\ncxl/features: bound fwctl command payload to the input buffer\n\nfwctl_cmd_rpc() copies cmd-\u003ein_len bytes into inbuf = kvzalloc(cmd-\u003ein_len)\nand passes inbuf and in_len to -\u003efw_rpc(). The CXL callback cxlctl_fw_rpc()\nignores in_len and never checks the user-controlled op_size against it.\n\ncxlctl_set_feature() bounds op_size only from below\n(op_size \u003c= sizeof(feat_in-\u003ehdr)) and then reads op_size - sizeof(hdr)\nbytes from feat_in-\u003efeat_data via cxl_set_feature(). With a small in_len\nand a large op_size the first memcpy() already reads past the\nkvzalloc(in_len) buffer; the out-of-bounds bytes are placed in the mailbox\npayload and sent to the device, and a large enough op_size can walk into\nunmapped memory and oops the kernel. The Get paths pin op_size to a fixed\nsize but likewise read the input struct without checking in_len.\n\nReject, at the single dispatch point, any request whose fixed header plus\nop_size does not fit in the copied-in buffer. The lower-bound test guards\nthe subtraction and ensures op_size was copied in before it is read.",
"id": "GHSA-x7fx-9652-j55v",
"modified": "2026-09-13T09:32:19Z",
"published": "2026-09-11T21:31:32Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89571"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/14d52c15d5d99477b20a2d61fe36f347080da6cd"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/d8957545fe96f7905791c937758ebfc1ae1e5b17"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/f687394af983df5660b6afae7e0d06969f3af206"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
"type": "CVSS_V3"
}
]
}
Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.
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.
Vulnerability timeline
Sightings and recorded dates, grouped by day · UTC
How durations are calculated
Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.
Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.
Loading timeline…
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.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.