Red Hat Security Advisory: xorg-x11-server security update
A heap buffer overflow vulnerability (CVE-2026-55999) exists in the glamor Font Atlas component of the X.Org X11 server. This vulnerability affects Red Hat Enterprise Linux 8 and related products. Red Hat has issued a security advisory with an update to address this issue. The vulnerability is rated as important by Red Hat Product Security. The advisory provides updated packages to remediate the flaw.
AI Analysis
Technical Summary
CVE-2026-55999 is a heap buffer overflow vulnerability in the glamor Font Atlas implementation within the X.Org X11 server. This flaw could potentially lead to memory corruption. Red Hat has released an updated xorg-x11-server package for Red Hat Enterprise Linux 8 and related variants to fix this issue. The advisory classifies the security impact as important and provides multiple updated RPM packages for different architectures. No CVSS score is provided in the advisory, but the severity is assessed as high.
Potential Impact
The heap buffer overflow vulnerability could allow an attacker to cause memory corruption within the X.Org X11 server process. This may lead to denial of service or potentially arbitrary code execution depending on exploitation. The advisory rates the impact as important, indicating a significant security concern for affected systems running the vulnerable X11 server.
Mitigation Recommendations
Red Hat has released updated xorg-x11-server packages for Red Hat Enterprise Linux 8 and related products that address CVE-2026-55999. Users should apply the security update as described in the Red Hat advisory RHSA-2026:38487 and the referenced article https://access.redhat.com/articles/11258 to remediate this vulnerability. Since this is an official fix, applying the update is the recommended mitigation.
Red Hat Security Advisory: xorg-x11-server security update
Description
A heap buffer overflow vulnerability (CVE-2026-55999) exists in the glamor Font Atlas component of the X.Org X11 server. This vulnerability affects Red Hat Enterprise Linux 8 and related products. Red Hat has issued a security advisory with an update to address this issue. The vulnerability is rated as important by Red Hat Product Security. The advisory provides updated packages to remediate the flaw.
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-55999 is a heap buffer overflow vulnerability in the glamor Font Atlas implementation within the X.Org X11 server. This flaw could potentially lead to memory corruption. Red Hat has released an updated xorg-x11-server package for Red Hat Enterprise Linux 8 and related variants to fix this issue. The advisory classifies the security impact as important and provides multiple updated RPM packages for different architectures. No CVSS score is provided in the advisory, but the severity is assessed as high.
Potential Impact
The heap buffer overflow vulnerability could allow an attacker to cause memory corruption within the X.Org X11 server process. This may lead to denial of service or potentially arbitrary code execution depending on exploitation. The advisory rates the impact as important, indicating a significant security concern for affected systems running the vulnerable X11 server.
Mitigation Recommendations
Red Hat has released updated xorg-x11-server packages for Red Hat Enterprise Linux 8 and related products that address CVE-2026-55999. Users should apply the security update as described in the Red Hat advisory RHSA-2026:38487 and the referenced article https://access.redhat.com/articles/11258 to remediate this vulnerability. Since this is an official fix, applying the update is the recommended mitigation.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:38487
- Cve Count
- 1
- Additional Cves
- []
- Cvss Version
- null
Threat ID: 6a54ade268715ace438f5e67
Added to database: 07/13/2026, 09:20:34 UTC
Last enriched: 07/13/2026, 09:45:17 UTC
Last updated: 07/14/2026, 02:47:18 UTC
Views: 3
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