# CVE-2026-98142: drm/cirrus-qemu: Validate BAR0 size during probe

CVE-2026-98142 is fixed in 37 products on 1 platform, first by DEBIAN-CVE-2026-98142, released September 29, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-98142
- Priority: High
- CVSS: 7.8 (Moderate)
- EPSS: 0.0011
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 25, 2026
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-98142

## Description

In the Linux kernel, the following vulnerability has been resolved:  drm/cirrus-qemu: Validate BAR0 size during probe  The `cirrus-qemu` driver relies on `CIRRUS_VRAM_SIZE` (4 MB) to validate framebuffer sizes. However, during PCI probe, the driver mapped BAR0 without verifying that its size matches `CIRRUS_VRAM_SIZE`.  If a PCI device with a BAR0 smaller than 4 MB is bound to the driver, the mapped VRAM will be smaller than expected. Because validation checks assume 4 MB VRAM, framebuffers larger than the mapped memory can be created.  When the display plane is updated (e.g. during release), `cirrus_primary_plane_helper_atomic_update()` copies the framebuffer to VRAM using `drm_fb_memcpy()`. Writing past the end of the mapped I/O memory causes a supervisor write page fault:  BUG: unable to handle page fault for address: ffffc9000389c000 ... RIP: 0010:memcpy_toio+0x7c/0xe0 arch/x86/lib/iomem.c:110 ... Call Trace:  <TASK>  iosys_map_memcpy_to include/linux/iosys-map.h:285 [inline]  drm_fb_memcpy+0x325/0x5d0 drivers/gpu/drm/drm_format_helper.c:442  cirrus_primary_plane_helper_atomic_update+0x98a/0xb00  drivers/gpu/drm/tiny/cirrus-qemu.c:358  drm_atomic_helper_commit_planes+0x626/0xea0  drivers/gpu/drm/drm_atomic_helper.c:3038  drm_atomic_helper_commit_tail+0x60/0x510  drivers/gpu/drm/drm_atomic_helper.c:1989  commit_tail+0x2b1/0x3c0 drivers/gpu/drm/drm_atomic_helper.c:2074  drm_atomic_helper_commit+0xa77/0xb10  drivers/gpu/drm/drm_atomic_helper.c:2312  Fix this by validating in `cirrus_pci_probe()` that the PCI BAR0 resource is not less than `CIRRUS_VRAM_SIZE`, returning `-ENODEV` if it is less.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | kernel-uek ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-core ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-core ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-core ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-core ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-devel ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-devel ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-core ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-core ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-deprecated ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-deprecated ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-desktop ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-desktop ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-extra ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-extra ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-extra-netfilter ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-extra-netfilter ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-usb ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-usb ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-wireless ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-debug-modules-wireless ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-devel ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-devel ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-doc ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-doc ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-core ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-core ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-deprecated ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-deprecated ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-desktop ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-desktop ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-extra ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-extra ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-extra-netfilter ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-extra-netfilter ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-usb ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-usb ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-wireless ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-modules-wireless ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-tools ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek-tools ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-core ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-core ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-devel ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-devel ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-core ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-core ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-deprecated ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-deprecated ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-desktop ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-desktop ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-extra ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-extra ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-extra-netfilter ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-extra-netfilter ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-usb ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-usb ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-wireless ol 10 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | kernel-uek64k-modules-wireless ol 9 | 0:6.12.0-207.111.5.1.el9uek | [ELSA-2026-500374](https://patchblox.com/security/data/fix/linux/elsa-2026-500374.md) | Oct 7, 2026 |
| Linux | linux Debian 13.5 (trixie) | 6.12.111-1 | [DEBIAN-CVE-2026-98142](https://patchblox.com/security/data/fix/linux/debian-cve-2026-98142.md) | Sep 29, 2026 |
| Linux | linux Debian 14 | 7.2.7-1 | [DEBIAN-CVE-2026-98142](https://patchblox.com/security/data/fix/linux/debian-cve-2026-98142.md) | Sep 29, 2026 |
| Linux | linux-6.12 Debian 12.15 (bookworm) | 6.12.111-1~deb12u1 | [DEBIAN-CVE-2026-98142](https://patchblox.com/security/data/fix/linux/debian-cve-2026-98142.md) | Sep 29, 2026 |

---

Data as of 2026-11-08T06:59:42Z 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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