AI description
Automated description summarized from trusted sources.
CVE-2026-50259 describes a stack-based buffer overflow vulnerability affecting the X.Org X server and Xwayland. The flaw originates within the `_XkbSetMapChecks()` function, which utilizes a fixed-size stack buffer named `mapWidths[256]`. A client-controlled offset allows the helper function `CheckKeyTypes()` to write beyond the bounds of this buffer, resulting in a stack buffer overflow. This vulnerability could potentially be exploited to crash the server or to achieve privilege escalation if the X server is operating with root privileges.
- Description
- A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. _XkbSetMapChecks() declares a fixed-size stack buffer mapWidths[256] indexed by key type index. The helper function CheckKeyTypes() writes to this buffer at a client-controlled offset, allowing a stack buffer overflow. This may be used to crash the server, or for privilege escalation if the X server runs as root.
- Source
- secalert@redhat.com
- NVD status
- Modified
- Products
- x_server, xwayland, enterprise_linux
CVSS 3.1
- Type
- Secondary
- Base score
- 7.8
- Impact score
- 5.9
- Exploitability score
- 1.8
- Vector string
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Severity
- HIGH
- Hype score
- Not currently trending
[
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:x.org:x_server:*:*:*:*:*:*:*:*",
"matchCriteriaId": "2F16F762-98D6-437F-8771-0F6C70AF65FD",
"versionEndExcluding": "21.1.23",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:x.org:xwayland:*:*:*:*:*:*:*:*",
"matchCriteriaId": "ED4EB1F5-9BBA-4751-9BC6-1639C7E02E0C",
"versionEndExcluding": "24.1.12",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*",
"matchCriteriaId": "142AD0DD-4CF3-4D74-9442-459CE3347E3A",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*",
"matchCriteriaId": "F4CFF558-3C47-480D-A2F0-BABF26042943",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*",
"matchCriteriaId": "7F6FB57C-2BC7-487C-96DD-132683AEB35D",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*",
"matchCriteriaId": "D65C2163-CFC2-4ABB-8F4E-CB09CEBD006C",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
]