CVE-2025-26597
published 2025-02-25CVE-2025-26597: A buffer overflow flaw was found in X.Org and Xwayland. If XkbChangeTypesOfKey() is called with a 0 group, it will resize the key symbols table to 0 but leave…
PriorityP343high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.48%
38.6th percentile
A buffer overflow flaw was found in X.Org and Xwayland. If XkbChangeTypesOfKey() is called with a 0 group, it will resize the key symbols table to 0 but leave the key actions unchanged. If the same function is later called with a non-zero value of groups, this will cause a buffer overflow because the key actions are of the wrong size.
Affected
20 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | xorg-server | < xorg-server 2:21.1.7-3+deb12u9 (bookworm) | xorg-server 2:21.1.7-3+deb12u9 (bookworm) |
| debian | xwayland | < xorg-server 2:21.1.7-3+deb12u9 (bookworm) | xorg-server 2:21.1.7-3+deb12u9 (bookworm) |
| msrc | azl3_xorg-x11-server-xwayland_24.1.1-3_on_azure_linux_3.0 | — | — |
| msrc | azl3_xorg-x11-server-xwayland_24.1.6-1_on_azure_linux_3.0 | — | — |
| msrc | cbl2_xorg-x11-server_1.20.10-15_on_cbl_mariner_2.0 | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
| redhat | enterprise_linux | — | — |
| the_x.org_foundation | xorg-x11-server | — | — |
| x.org | x_server | < 21.1.23 | 21.1.23 |
| x.org | x_server | < 21.1.16 | 21.1.16 |
| x.org | xorg-server | >= 0 < 2:1.20.11-1+deb11u15 | 2:1.20.11-1+deb11u15 |
| x.org | xorg-server | >= 0 < 2:21.1.7-3+deb12u9 | 2:21.1.7-3+deb12u9 |
| x.org | xorg-server | >= 0 < 2:21.1.16-1 | 2:21.1.16-1 |
| x.org | xorg-server | >= 0 < 2:21.1.16-1 | 2:21.1.16-1 |
| x.org | xwayland | < 24.1.12 | 24.1.12 |
| x.org | xwayland | < 24.1.6 | 24.1.6 |
| x.org | xwayland | >= 0 < 2:24.1.6-1 | 2:24.1.6-1 |
| x.org | xwayland | >= 0 < 2:24.1.6-1 | 2:24.1.6-1 |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
vendor_redhat7.8HIGH
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Red Hat
xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: stack buffer overflow in XKB key types due to unchecked shift levels
vendor_redhat·2026-06-02·CVSS 7.8
CVE-2026-50258 [HIGH] CWE-121 xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: stack buffer overflow in XKB key types due to unchecked shift levels
xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: stack buffer overflow in XKB key types due to unchecked shift levels
A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. The X server has multiple stack buffers sized XkbMaxShiftLevel * XkbNumKbdGroups but CheckKeyTypes() does not verify or clamp non-canonical key types to XkbMaxShiftLevel. A client can change key types to excessive shift levels and trigger stack overflows. This is caused by an incomplete fix of CVE-2025-26597. This may be used to crash the server, or for privilege escalation if the X server runs as root.
Package: xorg-x11-server-Xwayland (Red Hat Enterprise Linux 10) - Affected
Package: xorg-x11-server (Red Hat Enterprise Linux 6) - Out of support scope
Package: xorg-x11-server (R
Ubuntu
X.Org X Server regression
vendor_ubuntu·2025-03-17
CVE-2025-26598 X.Org X Server regression
Title: X.Org X Server regression
Summary: Several security issues were fixed in X.Org X Server.
USN-7299-2 fix vulnerabilities in X.Org X Server. This fix caused
a regression in Ubuntu 16.04 LTS and Ubuntu 18.04 LTS. This update
fix the regression and re-apply the fix for the CVE listed.
We apologize for the inconvenience.
Original advisory details:
Jan-Niklas Sohn discovered that the X.Org X Server incorrectly handled
certain memory operations. An attacker could use these issues to cause the
X Server to crash, leading to a denial of service, or possibly execute
arbitrary code.
Instructions: After a standard system update you need to reboot your computer to make all
the necessary changes.
Ubuntu
X.Org X Server vulnerabilities
vendor_ubuntu·2025-03-10
CVE-2025-26594 X.Org X Server vulnerabilities
Title: X.Org X Server vulnerabilities
Summary: Several security issues were fixed in X.Org X Server.
USN-7299-1 fixed several vulnerabilities in X.Org. This update provides
the corresponding update for Ubuntu 16.04 LTS and Ubuntu 18.04 LTS.
Original advisory details:
Jan-Niklas Sohn discovered that the X.Org X Server incorrectly handled
certain memory operations. An attacker could use these issues to cause the
X Server to crash, leading to a denial of service, or possibly execute
arbitrary code.
Instructions: After a standard system update you need to reboot your computer to make all
the necessary changes.
BSD
OpenBSD 7.5 Errata 018: SECURITY FIX
bsd_advisories·2025-02-25·CVSS 7.8
CVE-2025-26594 [HIGH] OpenBSD 7.5 Errata 018: SECURITY FIX
OpenBSD 7.5 Errata 018: SECURITY FIX
018: SECURITY FIX: February 25, 2025
All architectures Multiple X server issues. CVE-2025-26594 CVE-2025-26595 CVE-2025-26596 CVE-2025-26597 CVE-2025-26598 CVE-2025-26599 CVE-2025-26600 CVE-2025-26601
Ubuntu
X.Org X Server vulnerabilities
vendor_ubuntu·2025-02-25
CVE-2025-26595 X.Org X Server vulnerabilities
Title: X.Org X Server vulnerabilities
Summary: Several security issues were fixed in X.Org X Server.
Jan-Niklas Sohn discovered that the X.Org X Server incorrectly handled
certain memory operations. An attacker could use these issues to cause the
X Server to crash, leading to a denial of service, or possibly execute
arbitrary code.
Instructions: After a standard system update you need to reboot your computer to make all
the necessary changes.
Red Hat
xorg: xwayland: Buffer overflow in XkbChangeTypesOfKey()
vendor_redhat·2025-02-25·CVSS 7.8
CVE-2025-26597 [HIGH] CWE-119 xorg: xwayland: Buffer overflow in XkbChangeTypesOfKey()
xorg: xwayland: Buffer overflow in XkbChangeTypesOfKey()
A buffer overflow flaw was found in X.Org and Xwayland. If XkbChangeTypesOfKey() is called with a 0 group, it will resize the key symbols table to 0 but leave the key actions unchanged. If the same function is later called with a non-zero value of groups, this will cause a buffer overflow because the key actions are of the wrong size.
A buffer overflow flaw was found in X.Org and Xwayland. If XkbChangeTypesOfKey() is called with a 0 group, it will resize the key symbols table to 0 but leave the key actions unchanged. If the same function is later called with a non-zero value of groups, this will cause a buffer overflow because the key actions are of the wrong size.
Statement: Xorg server does not run with root privileges in Red Ha
Microsoft
Xorg: xwayland: buffer overflow in xkbchangetypesofkey()
vendor_msrc·2025-02-11·CVSS 7.8
CVE-2025-26597 [HIGH] CWE-119 Xorg: xwayland: buffer overflow in xkbchangetypesofkey()
Xorg: xwayland: buffer overflow in xkbchangetypesofkey()
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
redhat: redhat
Customer Action Required: Yes
Remediation: CBL-Mariner Releases
Reference: https://le
Debian
CVE-2025-26597: xorg-server - A buffer overflow flaw was found in X.Org and Xwayland. If XkbChangeTypesOfKey()...
vendor_debian·2025·CVSS 7.8
CVE-2025-26597 [HIGH] CVE-2025-26597: xorg-server - A buffer overflow flaw was found in X.Org and Xwayland. If XkbChangeTypesOfKey()...
A buffer overflow flaw was found in X.Org and Xwayland. If XkbChangeTypesOfKey() is called with a 0 group, it will resize the key symbols table to 0 but leave the key actions unchanged. If the same function is later called with a non-zero value of groups, this will cause a buffer overflow because the key actions are of the wrong size.
Scope: local
bookworm: resolved (fixed in 2:21.1.7-3+deb12u9)
bullseye: resolved (fixed in 2:1.20.11-1+deb11u15)
forky: resolved (fixed in 2:21.1.16-1)
sid: resolved (fixed in 2:21.1.16-1)
trixie: resolved (fixed in 2:21.1.16-1)
GHSA
A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland.
ghsa_unreviewed·2026-06-05·CVSS 7.8
CVE-2026-50258 [HIGH] CWE-121 A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland.
A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. The X server has multiple stack buffers sized XkbMaxShiftLevel * XkbNumKbdGroups but CheckKeyTypes() does not verify or clamp non-canonical key types to XkbMaxShiftLevel. A client can change key types to excessive shift levels and trigger stack overflows. This is caused by an incomplete fix of CVE-2025-26597. This may be used to crash the server, or for privilege escalation if the X server runs as root.
OSV
CVE-2025-26597: A buffer overflow flaw was found in X
osv·2025-02-25·CVSS 7.8
CVE-2025-26597 [HIGH] CVE-2025-26597: A buffer overflow flaw was found in X
A buffer overflow flaw was found in X.Org and Xwayland. If XkbChangeTypesOfKey() is called with a 0 group, it will resize the key symbols table to 0 but leave the key actions unchanged. If the same function is later called with a non-zero value of groups, this will cause a buffer overflow because the key actions are of the wrong size.
GHSA
GHSA-7qjx-378m-p8hm: A buffer overflow flaw was found in X
ghsa_unreviewed·2025-02-25
CVE-2025-26597 [HIGH] CWE-119 GHSA-7qjx-378m-p8hm: A buffer overflow flaw was found in X
A buffer overflow flaw was found in X.Org and Xwayland. If XkbChangeTypesOfKey() is called with a 0 group, it will resize the key symbols table to 0 but leave the key actions unchanged. If the same function is later called with a non-zero value of groups, this will cause a buffer overflow because the key actions are of the wrong size.
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-50258 xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: stack buffer overflow in XKB key types due to unchecked shift levels
bugzilla·2026-06-05·CVSS 7.8
CVE-2026-50258 [HIGH] CVE-2026-50258 xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: stack buffer overflow in XKB key types due to unchecked shift levels
CVE-2026-50258 xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: stack buffer overflow in XKB key types due to unchecked shift levels
The X server has multiple stack buffers sized XkbMaxShiftLevel * XkbNumKbdGroups but CheckKeyTypes() does not verify or clamp non-canonical key types to XkbMaxShiftLevel. A client can change key types to excessive shift levels and trigger three separate stack overflows.
This is caused by an incomplete fix of CVE-2025-26597.
Any X client that can connect to the server can trigger this issue. This may be used to crash the server, or for privilege escalation if the X server runs as root.
Components affected: xorg-x11-server, xorg-x11-server-Xwayland
Versions affected: xorg-x11-server <= 21.1.22, xorg-x11-server-Xwayland <= 24.1.9
Fixed upstream i
Bugzilla
CVE-2025-26597 xorg: xwayland: Buffer overflow in XkbChangeTypesOfKey()
bugzilla·2025-02-12·CVSS 7.8
CVE-2025-26597 [HIGH] CVE-2025-26597 xorg: xwayland: Buffer overflow in XkbChangeTypesOfKey()
CVE-2025-26597 xorg: xwayland: Buffer overflow in XkbChangeTypesOfKey()
If XkbChangeTypesOfKey() is called with 0 group, it will resize the key
symbols table to 0 but leave the key actions unchanged.
If later, the same function is called with a non-zero value of groups,
this will cause a buffer overflow because the key actions are of the wrong
size.
Discussion:
This issue has been addressed in the following products:
Red Hat Enterprise Linux 9
Via RHSA-2025:2500 https://access.redhat.com/errata/RHSA-2025:2500
---
This issue has been addressed in the following products:
Red Hat Enterprise Linux 8
Via RHSA-2025:2502 https://access.redhat.com/errata/RHSA-2025:2502
---
This issue has been addressed in the following products:
Red Hat Enterprise Linux 8.2 Advanced Update Support
Vi
https://access.redhat.com/errata/RHSA-2025:2500https://access.redhat.com/errata/RHSA-2025:2502https://access.redhat.com/errata/RHSA-2025:2861https://access.redhat.com/errata/RHSA-2025:2862https://access.redhat.com/errata/RHSA-2025:2865https://access.redhat.com/errata/RHSA-2025:2866https://access.redhat.com/errata/RHSA-2025:2873https://access.redhat.com/errata/RHSA-2025:2874https://access.redhat.com/errata/RHSA-2025:2875https://access.redhat.com/errata/RHSA-2025:2879https://access.redhat.com/errata/RHSA-2025:2880https://access.redhat.com/errata/RHSA-2025:3976https://access.redhat.com/errata/RHSA-2025:7163https://access.redhat.com/errata/RHSA-2025:7165https://access.redhat.com/errata/RHSA-2025:7458https://access.redhat.com/security/cve/CVE-2025-26597https://bugzilla.redhat.com/show_bug.cgi?id=2345255http://www.openwall.com/lists/oss-security/2026/06/02/1https://lists.debian.org/debian-lts-announce/2025/02/msg00036.html
2025-02-25
Published