Description
A buffer overread caused by an integer-overflow in Proc/SProcXResQueryClientIds in X.Org xwayland before 24.1.15 and X Server before 21.1.26 could be used by attackers on authenticated X clients to crash the server or leak out information.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| X.Org | xorg-x11-server | < 21.1.26 | 21.1.26 |
| X.Org | xwayland | < 24.1.15 | 24.1.15 |
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 | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 16.0 | xorg-x11-server | 21.1.15-160000.7.1 | openSUSE-SU-2026:22274-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | xorg-server | 21.1.26-r0 | — |
| Alpine v3.24 | xwayland | 24.1.15-r0 | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | wayland +2 | No fix yet | — |
Advisories 2
- openSUSE-SU-2026:22274-1 Security update for xorg-x11-server SUSE / openSUSE Security Updates · Nov 14, 2026
- WID-SEC-2026-4511 Xwayland und X.Org X Server: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026