title: Xorg-x11-server: user-after-free in procrenderaddglyphs
description: A use-after-free vulnerability was found in the ProcRenderAddGlyphs() function of Xorg servers. This issue occurs when AllocateGlyph() is called to store new glyphs sent by the client to the X server, potentially resulting in multiple entries pointing to the same non-refcounted glyphs. Consequently, ProcRenderAddGlyphs() may free a glyph, leading to a use-after-free scenario when the same glyph pointer is subsequently accessed. This flaw allows an authenticated attacker to execute arbitrary code on the system by sending a specially crafted request.
problem types: Use After Free
affected:
{
product: xorg-server
vendor: n/a
versions:
version: 21.1.12, status: unaffected
}
{
product: xwayland
vendor: n/a
versions:
version: 23.2.5, status: unaffected
}
{
vendor: Red Hat
product: Red Hat Enterprise Linux 6
collectionURL: https://access.redhat.com/downloads/content/package-browser/
packageName: tigervnc
defaultStatus: unknown
cpes: cpe:/o:redhat:enterprise_linux:6
}
{
vendor: Red Hat
product: Red Hat Enterprise Linux 6
collectionURL: https://access.redhat.com/downloads/content/package-browser/
packageName: xorg-x11-server
defaultStatus: unknown
cpes: cpe:/o:redhat:enterprise_linux:6
}
{
vendor: Red Hat
product: Red Hat Enterprise Linux 7
collectionURL: https://access.redhat.com/downloads/content/package-browser/
packageName: tigervnc
defaultStatus: affected
cpes: cpe:/o:redhat:enterprise_linux:7
}
{
vendor: Red Hat
product: Red Hat Enterprise Linux 7
collectionURL: https://access.redhat.com/downloads/content/package-browser/
packageName: xorg-x11-server
defaultStatus: affected
cpes: cpe:/o:redhat:enterprise_linux:7
}
{
vendor: Red Hat
product: Red Hat Enterprise Linux 8
collectionURL: https://access.redhat.com/downloads/content/package-browser/
packageName: tigervnc
defaultStatus: affected
cpes: cpe:/o:redhat:enterprise_linux:8
}
{
vendor: Red Hat
product: Red Hat Enterprise Linux 8
collectionURL: https://access.redhat.com/downloads/content/package-browser/
packageName: xorg-x11-server
defaultStatus: affected
cpes: cpe:/o:redhat:enterprise_linux:8
}
{
vendor: Red Hat
product: Red Hat Enterprise Linux 8
collectionURL: https://access.redhat.com/downloads/content/package-browser/
packageName: xorg-x11-server-Xwayland
defaultStatus: affected
cpes: cpe:/o:redhat:enterprise_linux:8
}
{
vendor: Red Hat
product: Red Hat Enterprise Linux 9
collectionURL: https://access.redhat.com/downloads/content/package-browser/
packageName: tigervnc
defaultStatus: affected
cpes: cpe:/o:redhat:enterprise_linux:9
}
{
vendor: Red Hat
product: Red Hat Enterprise Linux 9
collectionURL: https://access.redhat.com/downloads/content/package-browser/
packageName: xorg-x11-server
defaultStatus: affected
cpes: cpe:/o:redhat:enterprise_linux:9
}
{
vendor: Red Hat
product: Red Hat Enterprise Linux 9
collectionURL: https://access.redhat.com/downloads/content/package-browser/
packageName: xorg-x11-server-Xwayland
defaultStatus: affected
cpes: cpe:/o:redhat:enterprise_linux:9
}
{
product: Fedora
vendor: Fedora
collectionURL: https://packages.fedoraproject.org/
packageName: xorg-x11-server-Xwayland
defaultStatus: affected
}
{
product: Fedora
vendor: Fedora
collectionURL: https://packages.fedoraproject.org/
packageName: xorg-x11-server
defaultStatus: affected
}
{
product: Fedora
vendor: Fedora
collectionURL: https://packages.fedoraproject.org/
packageName: tigervnc
defaultStatus: affected
}
metrics:
other: [
content: {'value': 'Important', 'namespace': 'https://access.redhat.com/security/updates/classification/'}
type: Red Hat severity rating
]
workarounds: Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.