dbcve.org
Enterprise Linux EusOperating system · Redhat

CVE-2023-6478

HIGH · 7.5 CVSS v3.1 Published 2023-12-13
Fix available
A fix is available. Upgrade to 21.1.10 / 23.2.3 or later.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A flaw was found in xorg-server. A specially crafted request to RRChangeProviderProperty or RRChangeOutputProperty can trigger an integer overflow which may lead to a disclosure of sensitive information.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis
How this class of weakness works · CWE-190

An arithmetic operation produces a value too large for its type and wraps around to an unexpected — often tiny or negative — number. That miscalculated value then drives a memory allocation or a bounds check, opening the door to corruption. The fix is checked arithmetic and validating sizes before they're used.

General guidance for the integer overflow class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Enterprise Linux EusOperating system
Affected:= 9.2
Debian LinuxOperating system
Affected:= 10.0= 11.0= 12.0
X ServerApplication
Affected:< 21.1.10
XwaylandApplication
Affected:< 23.2.3
TigervncApplication
Affected:all versions

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 21.1.10 / 23.2.3 or later
Fixed in 21.1.1023.2.3
Vendor patch gitlab.freedesktop.org →
Recommended fix High confidence

X Server 21.1.10, Xwayland 23.2.3

  1. 1. Identify which component is affected: X Server, Xwayland, or Tigervnc in your environment
  2. 2. For X Server: Upgrade to version 21.1.10 or later
  3. 3. For Xwayland: Upgrade to version 23.2.3 or later
  4. 4. For Tigervnc: Upgrade to a version that includes the patched X server code (contact vendor for specific version)
  5. 5. After applying the update, restart the X server or display manager service
  6. 6. Verify the installed version matches or exceeds the fixed release

Generated from the published advisory — verify against the referenced sources before acting.

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $3,200. Get the upgrade done

Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2023-6478 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data