A use-after-free flaw was found in the X.Org X server and Xwayland in CreateSaverWindow(). A client can trigger a use-after-free read after changing window attributes and forcing the screen saver, leading to information disclosure.
{
"cwe_ids": [
"CWE-416"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/50xxx/CVE-2026-50263.json",
"cna_assigner": "redhat"
}{
"cpe": [
"cpe:2.3:a:x.org:x_server:*:*:*:*:*:*:*:*",
"cpe:2.3:a:x.org:xwayland:*:*:*:*:*:*:*:*",
"cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*"
],
"source": [
"CPE_RANGE",
"CPE_STRING",
"REFERENCES"
],
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "21.1.23"
},
{
"fixed": "24.1.12"
},
{
"introduced": "7.0"
},
{
"last_affected": "7.0"
}
]
}"2026-07-29T08:20:16Z"
[
{
"signature_type": "Function",
"target": {
"file": "Xext/saver.c",
"function": "CreateSaverWindow"
},
"deprecated": false,
"source": "https://gitlab.freedesktop.org/xorg/xserver@ecc634f1b2f7aa473d3a267eada98c4918bf9e05",
"id": "CVE-2026-50263-4e7c26c1",
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"source": "https://gitlab.freedesktop.org/xorg/xserver@ecc634f1b2f7aa473d3a267eada98c4918bf9e05",
"id": "CVE-2026-50263-9944a510",
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{
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"target": {
"file": "Xext/saver.c",
"function": "ScreenSaverFreeAttr"
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"source": "https://gitlab.freedesktop.org/xorg/xserver@ecc634f1b2f7aa473d3a267eada98c4918bf9e05",
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"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-50263.json"