# CVE-2026-98526: llc: reserve device headroom for allocated frames

CVE-2026-98526 is fixed in 2 products on 1 platform, first by DEBIAN-CVE-2026-98526, released October 19, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-98526
- Priority: High
- CVSS: 8.3 (Important)
- EPSS: 0.0022
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 18, 2026
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-98526

## Description

In the Linux kernel, the following vulnerability has been resolved:  llc: reserve device headroom for allocated frames  llc_alloc_frame() reserves link-layer headroom using the device type. This is insufficient for stacked Ethernet devices such as VLAN devices, where vlan_dev_hard_header() pushes a VLAN header before the lower device's Ethernet header. An LLC response on such a device can therefore underflow skb headroom in eth_header().  Use LL_RESERVED_SPACE() to account for the device's actual required headroom while preserving the existing LLC device-type check.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 6.1.190-1 | [DEBIAN-CVE-2026-98526](https://patchblox.com/security/data/fix/linux/debian-cve-2026-98526.md) | Oct 19, 2026 |
| Linux | linux Debian 13.5 (trixie) | 6.12.113-1 | [DEBIAN-CVE-2026-98526](https://patchblox.com/security/data/fix/linux/debian-cve-2026-98526.md) | Oct 19, 2026 |
| Linux | linux Debian 14 | 7.2.9-1 | [DEBIAN-CVE-2026-98526](https://patchblox.com/security/data/fix/linux/debian-cve-2026-98526.md) | Oct 19, 2026 |
| Linux | linux-6.12 Debian 12.15 (bookworm) | 6.12.113-1~deb12u1 | [DEBIAN-CVE-2026-98526](https://patchblox.com/security/data/fix/linux/debian-cve-2026-98526.md) | Oct 19, 2026 |

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Data as of 2026-11-08T00:53:09Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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