Red Hat Security Advisory: tigervnc security update
Multiple security vulnerabilities have been identified in the X.Org Xwayland component used by TigerVNC, a remote display system. These include use-after-free, buffer overflow, heap overflow, out-of-bounds write, and use of uninitialized pointer issues. The vulnerabilities affect Red Hat Enterprise Linux Server 6 and its Extended Life Cycle Support Extension. Red Hat has issued a security advisory with updates to address these issues.
AI Analysis
Technical Summary
TigerVNC, a suite of VNC servers and clients, relies on X.Org's Xwayland component for remote display functionality. Several vulnerabilities have been discovered in Xwayland, including use-after-free bugs (CVE-2025-26594, CVE-2025-26600, CVE-2025-26601), buffer overflows (CVE-2025-26595, CVE-2025-26597), a heap overflow (CVE-2025-26596), out-of-bounds write (CVE-2025-26598), and use of uninitialized pointer (CVE-2025-26599). These issues could potentially lead to memory corruption and instability. Red Hat has released security updates for Red Hat Enterprise Linux Server 6 and its Extended Life Cycle Support Extension to fix these vulnerabilities.
Potential Impact
The vulnerabilities involve memory corruption issues such as use-after-free, buffer overflow, heap overflow, out-of-bounds write, and use of uninitialized pointers in the Xwayland component. These could lead to crashes or potentially allow an attacker to execute arbitrary code or cause denial of service. The advisory rates the security impact as Important (high severity). There are no known exploits in the wild at the time of the advisory.
Mitigation Recommendations
Red Hat has issued security updates for affected Red Hat Enterprise Linux Server 6 and Extended Life Cycle Support Extension packages. Users should apply these updates promptly after ensuring all previous errata relevant to their system have been applied. Detailed update instructions are available from Red Hat's official documentation. No alternative mitigations or workarounds are specified.
Red Hat Security Advisory: tigervnc security update
Description
Multiple security vulnerabilities have been identified in the X.Org Xwayland component used by TigerVNC, a remote display system. These include use-after-free, buffer overflow, heap overflow, out-of-bounds write, and use of uninitialized pointer issues. The vulnerabilities affect Red Hat Enterprise Linux Server 6 and its Extended Life Cycle Support Extension. Red Hat has issued a security advisory with updates to address these issues.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
TigerVNC, a suite of VNC servers and clients, relies on X.Org's Xwayland component for remote display functionality. Several vulnerabilities have been discovered in Xwayland, including use-after-free bugs (CVE-2025-26594, CVE-2025-26600, CVE-2025-26601), buffer overflows (CVE-2025-26595, CVE-2025-26597), a heap overflow (CVE-2025-26596), out-of-bounds write (CVE-2025-26598), and use of uninitialized pointer (CVE-2025-26599). These issues could potentially lead to memory corruption and instability. Red Hat has released security updates for Red Hat Enterprise Linux Server 6 and its Extended Life Cycle Support Extension to fix these vulnerabilities.
Potential Impact
The vulnerabilities involve memory corruption issues such as use-after-free, buffer overflow, heap overflow, out-of-bounds write, and use of uninitialized pointers in the Xwayland component. These could lead to crashes or potentially allow an attacker to execute arbitrary code or cause denial of service. The advisory rates the security impact as Important (high severity). There are no known exploits in the wild at the time of the advisory.
Mitigation Recommendations
Red Hat has issued security updates for affected Red Hat Enterprise Linux Server 6 and Extended Life Cycle Support Extension packages. Users should apply these updates promptly after ensuring all previous errata relevant to their system have been applied. Detailed update instructions are available from Red Hat's official documentation. No alternative mitigations or workarounds are specified.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2025:3976
- Cve Count
- 8
- Additional Cves
- ["CVE-2025-26595","CVE-2025-26596","CVE-2025-26597","CVE-2025-26598","CVE-2025-26599","CVE-2025-26600","CVE-2025-26601"]
- Cvss Version
- null
Threat ID: 6a3da1d54853345fc1826e7c
Added to database: 06/25/2026, 21:47:01 UTC
Last enriched: 06/25/2026, 22:14:47 UTC
Last updated: 07/01/2026, 15:51:10 UTC
Views: 4
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