CVE-2022-46340Network attack vector

Code execution via oversized GenericEvent stack overwrite

Published Dec 14, 2022 · Updated Apr 22, 2025

Stack-based buffer overflow in X.Org Server before 21.1.5 allows attackers to execute code via a crafted XTestFakeInput request. XTestSwapFakeInput assumes every event is 32 bytes and swaps an oversized GenericEvent into a 32-byte stack object, corrupting adjacent stack memory. Exploitation requires opposite byte order between client and server; impact is privilege escalation for privileged servers or code execution through SSH X forwarding.

CVSS severity8.8
High
EPSS probability2.48%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack-based buffer overflow in X.Org Server before 21.1.5 allows attackers to execute code via a crafted XTestFakeInput request. XTestSwapFakeInput assumes every event is 32 bytes and swaps an oversized GenericEvent into a 32-byte stack object, corrupting adjacent stack memory. Exploitation requires opposite byte order between client and server; impact is privilege escalation for privileged servers or code execution through SSH X forwarding.

The record

CVE
CVE-2022-46340
Published
Dec 14, 2022
Updated
Apr 22, 2025
Vendor
X.Org
Product
X.Org Server
Classifications
CWE-787, T1068
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 14, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 22, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=xorg-x11-server-1.20.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

X.Org · X.Org Serverversion=xorg-x11-server-1.20.4

Published CVSS scores

7.8Zero Day InitiativeCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
8.8Amazon LinuxCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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