Xorg-X11-Server Security Update — AlmaLinux 9 (ALSA-2026:38486)
This is a security release for AlmaLinux 9. The fix ships in the current release line (referenced builds: 20.11-34). Update the product on every affected server to the patched release — there is no workaround, and unpatched servers remain exposed until updated.
Fix Commands
EL8+ (AlmaLinux/CloudLinux/Rocky)
sudo dnf update
What this means under a SharedLicense license
Your SharedLicense license itself is not affected — this is a change in AlmaLinux 9 software, not in licensing. Update the product through its standard update channel. Licenses keep working through updates; nothing needs re-issuing or re-activating.
X.Org is an open-source implementation of the X Window System. It provides the basic low-level functionality that full-fledged graphical user interfaces are designed upon.
Security Fix(es):
* xorg: X11: xserver: X.org: glamor Font Atlas Heap Buffer Overflow (CVE-2026-55999)
For more details about the secur…
Type:
security
Severity:
important
Release date:
2026-07-14
Description:
X.Org is an open-source implementation of the X Window System. It provides the basic low-level functionality that full-fledged graphical user interfaces are designed upon.
Security Fix(es):
* xorg: X11: xserver: X.org: glamor Font Atlas Heap Buffer Overflow (CVE-2026-55999)
For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
References:
Updated packages listed below:
| Architecture | Package | Checksum |
| aarch64 | xorg-x11-server-Xephyr-1.20.11-34.el9_8.3.aarch64.rpm | 3112a589fb07117e0632e1280b951ea313ac7b3c461b1d852932ca7a46de6430 |
| aarch64 | xorg-x11-server-common-1.20.11-34.el9_8.3.aarch64.rpm | 3410bccd65604484bda4ec24e7aff4fd8c2152e344445c9d1c72afa0393ab16a |
| aarch64 | xorg-x11-server-Xnest-1.20.11-34.el9_8.3.aarch64.rpm | 4ecde60b2149c7936af9caa4a73281fb7bc70f990e285652cd8e82fb4b488c72 |
| aarch64 | xorg-x11-server-Xdmx-1.20.11-34.el9_8.3.aarch64.rpm | 5e050177f2b3fcbce81aeb70eb9b8003ee2fa94709daaed913b9896ba999aae0 |
| aarch64 | xorg-x11-server-Xvfb-1.20.11-34.el9_8.3.aarch64.rpm | 70eeed3a70f6c2c888932489947fcde04e06344d10f70fdccc98dc55d40cccab |
| aarch64 | xorg-x11-server-devel-1.20.11-34.el9_8.3.aarch64.rpm | 7d62bd940b44a8fc3ec71518d4973ec7c532ccfc8efbbb3377b0f182328d725d |
| aarch64 | xorg-x11-server-Xorg-1.20.11-34.el9_8.3.aarch64.rpm | f5bba53d03723b2131935649907a54e57b669d9df54504cc94d001b1bcaf1e3a |
| i686 | xorg-x11-server-devel-1.20.11-34.el9_8.3.i686.rpm | ad3194069c6e7a1823d1d69715314eb9e01aa069b510161e15699a53ff2311ea |
| noarch | xorg-x11-server-source-1.20.11-34.el9_8.3.noarch.rpm | 48499a138a6f93c1ab1264a01a39bb13c0536e0479c9928d112ae873477ec932 |
| ppc64le | xorg-x11-server-Xnest-1.20.11-34.el9_8.3.ppc64le.rpm | 1f1b91d4af9390a8fa8c1fb61372b110fa751f7a6857eb82b83cf950f4b69cb7 |
| ppc64le | xorg-x11-server-Xvfb-1.20.11-34.el9_8.3.ppc64le.rpm | 3d7b99c37d4bb9fcb6cb587b1c4326167b626bcad8b3f9a221d409c936cd74ee |
| ppc64le | xorg-x11-server-Xdmx-1.20.11-34.el9_8.3.ppc64le.rpm | 3f5774f2e2dec836bb220b9d51169a21dd76f3255ba018860a0da412439baf18 |
| ppc64le | xorg-x11-server-Xephyr-1.20.11-34.el9_8.3.ppc64le.rpm | 82df36d9887482b1a72ef5cd141d0b3c9e7bd42fd8223b458f24fdc87b492a2d |
| ppc64le | xorg-x11-server-Xorg-1.20.11-34.el9_8.3.ppc64le.rpm | ca6685c65aad9a90a76a7a845fa0343337f59cd0f3339c37698ac5b0daaa7d87 |
| ppc64le | xorg-x11-server-common-1.20.11-34.el9_8.3.ppc64le.rpm | d4168feaeeabe6ed0fb54a8036ab2b550b39b58f275120abc1f6e724491418ea |
| ppc64le | xorg-x11-server-devel-1.20.11-34.el9_8.3.ppc64le.rpm | e0611eaa793eda4d10f6bed868d16695e84f6883cc0f89639841590b9d9699fd |
| s390x | xorg-x11-server-Xvfb-1.20.11-34.el9_8.3.s390x.rpm | 64ecd20679fee8bcb9de33ba21e84c06c53e74825e1d991934f0ddd2239e3a0d |
| s390x | xorg-x11-server-Xorg-1.20.11-34.el9_8.3.s390x.rpm | 785c87c8220ca9850c816030802159b369bef4a76c8fcafb35e9ccfccbf5bfee |
| s390x | xorg-x11-server-common-1.20.11-34.el9_8.3.s390x.rpm | 9cdb84ad57fc7b771d427dbcec3b098d90c2fd204ad844afed5c22bd7cf21e4e |
| s390x | xorg-x11-server-Xnest-1.20.11-34.el9_8.3.s390x.rpm | aa5022adcb45dbf9dcc081935a7f05ca11e5a099d501f16eeb5974de48c2929d |
| s390x | xorg-x11-server-Xdmx-1.20.11-34.el9_8.3.s390x.rpm | ada4f29b21afaa5438d859cc69f190cbe151e98cedf37d6026ecbb4c82018db5 |
| s390x | xorg-x11-server-Xephyr-1.20.11-34.el9_8.3.s390x.rpm | e97ae3a28b3c82aef9f26cb4a0abf6282894dcbe448e56f9694a77f95b9a46f6 |
| s390x | xorg-x11-server-devel-1.20.11-34.el9_8.3.s390x.rpm | facc020114b01c2ea7c54942ebe9ae392522ec0612a57c923ec5645e3e7f425c |
| x86_64 | xorg-x11-server-Xnest-1.20.11-34.el9_8.3.x86_64.rpm | 1d3a9450944d547914d8109bafac818d1ea11dd44712c2aaee4f59df29bdd8ee |
| x86_64 | xorg-x11-server-devel-1.20.11-34.el9_8.3.x86_64.rpm | 59173bc9c8210d8b9051e075f99cda8aa73032e6f9dfce1d4aec834086c7d743 |
| x86_64 | xorg-x11-server-Xorg-1.20.11-34.el9_8.3.x86_64.rpm | 82b9d26d1a9d3681831813b3a90b00ba775207089fa3c6c620819421de8ebcd1 |
| x86_64 | xorg-x11-server-Xdmx-1.20.11-34.el9_8.3.x86_64.rpm | 876df8d2343f806db798a49e176aa752b8ac890a22d4a1ed8afaf5f0787b4277 |
| x86_64 | xorg-x11-server-Xephyr-1.20.11-34.el9_8.3.x86_64.rpm | a878faa2f3dbda0cf0f9680df1d18e430806f643dc2c7a1727132658146e9007 |
| x86_64 | xorg-x11-server-common-1.20.11-34.el9_8.3.x86_64.rpm | b92c5b02828b4877aa9a0fda14d14f091feb3d0d9019b279e5fd2675983a506f |
| x86_64 | xorg-x11-server-Xvfb-1.20.11-34.el9_8.3.x86_64.rpm | f1be7923ddeafef69c9db661c2d0d69c75097540db353f28540ba64ccf547d4a |
Notes:
This page is generated automatically from Red Hat security data and has not been checked for errors. For clarification or corrections please contact the AlmaLinux Packaging Team.
References
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