# CVE-2026-90223: nfc: llcp: bound SNL TLV parsing to the skb and add length checks

> A nearby NFC device can trigger out-of-bounds reads in the Linux kernel LLCP parser, potentially causing crashes or leaking memory.

- **Severity:** High 7.1 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 17 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-102746, BELL-CVE-2026-90223, DEBIAN-CVE-2026-90223, GHSA-jxpm-782w-87ph, UBUNTU-CVE-2026-90223

## What is CVE-2026-90223?

CVE-2026-90223 is a high-severity memory corruption vulnerability in Linux, published on 17 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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

nfc: llcp: bound SNL TLV parsing to the skb and add length checks

nfc_llcp_recv_snl() walked the SNL TLV list using a u16 offset/length
pair derived from skb->len, without bounding reads to the actual skb
data. Three problems followed:

  - For a short frame (skb->len < LLCP_HEADER_SIZE), tlv_len underflowed.
  - The per-TLV header (type, length) was read without checking that two
    bytes remained.
  - A declared TLV length could run past the end of the buffer, and an
    SDREQ with length == 0 made "service_name_len = length - 1" underflow
    (size_t), driving an out-of-bounds read in the following strncmp() /
    nfc_llcp_sock_from_sn(). The SDRES case likewise read tlv[2]/tlv[3]
    without a length check.

A nearby NFC device can reach this without authentication; LLCP link
activation happens automatically after NFC-DEP.

Walk the TLV list by pointer, bounded by skb_tail_pointer() over the
linear skb data, and validate each TLV declared length before use. Add
explicit length checks for SDREQ (>= 1) and SDRES (exactly 2).

Found by 0sec automated security-research tooling (https://0sec.ai).

## Which versions are affected by CVE-2026-90223?


## How do I fix CVE-2026-90223?

Apply the vendor's patch.

## Is CVE-2026-90223 being exploited?

There is no known exploitation of CVE-2026-90223 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-90223 and fix it if it is affected.

What it is: CVE-2026-90223 is a high-severity memory corruption vulnerability in Linux, published on 17 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-90223 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-90223/ (Markdown: https://insights.sbomify.com/CVE-2026-90223/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-90223
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-90223
- OSV: https://osv.dev/vulnerability/CVE-2026-90223

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-90223/
Summaries are generated and may contain mistakes; the official description above is the record.