Description
Incorrectly handled negative sizes when processing ProcXvShmPutImage requests in the X.Org xwayland before 24.1.15 and X Server before 21.1.26 could be used by local authenticated X clients to crash the X server or execute code.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| X.Org | xwayland | < 24.1.15 | 24.1.15 |
| X.Org | xorg-x11-server | < 21.1.26 | 21.1.26 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | xwayland +1 | No fix yet | — |
| Debian 13 | xwayland +1 | No fix yet | — |
| Debian 12 | xwayland +1 | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | xwayland +1 | No fix yet | — |
| Ubuntu 26.04 LTS | xwayland +1 | No fix yet | — |
| Ubuntu 24.04 LTS | xwayland +1 | No fix yet | — |
| Ubuntu 22.04 LTS | xwayland +1 | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | xorg-server | No fix yet | — |
| Ubuntu Pro 18.04 LTS | xorg-server +1 | No fix yet | — |
| Ubuntu Pro 16.04 LTS | xorg-server +1 | No fix yet | — |
| Ubuntu Pro 14.04 LTS | xorg-server | No fix yet | — |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | xorg-x11-server-Xorg +6 | 21.1.13-5.amzn2023.0.13 | ALAS2023-2026-3444 |
| Amazon Linux 2023 | xorg-x11-server-Xwayland +1 | 24.1.3-1.amzn2023.0.8 | ALAS2023-2026-3443 |
| Amazon Linux 2 | xorg-x11-server-Xdmx +8 | 1.20.4-22.amzn2.0.15 | ALAS2-2026-4108 |
Advisories 4
- WID-SEC-2026-4511 Xwayland und X.Org X Server: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- ALAS2023-2026-3443 Important: xorg-x11-server-Xwayland security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Nov 12, 2026
- ALAS2023-2026-3444 Important: xorg-x11-server security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Nov 12, 2026
- ALAS2-2026-4108 Important: xorg-x11-server security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Nov 12, 2026