CVE intelligence and bounded remediation

CVE-2017-13721 — X.Org X Server security vulnerability

Medium CVSS 4.7

In X.Org Server (aka xserver and xorg-server) before 1.19.4, an attacker authenticated to an X server with the X shared memory extension enabled can cause aborts of the X server or replace shared memory segments of other X clients in the same session.

Severity
Medium
CVSS
4.7 (3.0)
Published
2017-10-10
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-269

Affected products

  • x.org / x_server
  • debian / debian_linux / 8.0
  • debian / debian_linux / 9.0

Matched remediation archetype

Privilege escalation and unsafe privilege management

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Map service accounts, operating-system identities, roles, capabilities, impersonation, set-user transitions, and administrative helper paths.
  • Determine whether untrusted users or lower-privilege processes can reach the affected transition or modify inputs it trusts.
  • Review file, socket, registry, device, job, container, and cloud-role permissions used before and after privilege changes.

Remediate safely

  • Apply the supported fix and redesign privileged operations as a minimal, authenticated, allowlisted interface.
  • Drop privileges before processing untrusted input, verify the drop succeeds, and remove unnecessary roles, capabilities, and write permissions.
  • Validate ownership and permissions at time of use and add explicit lower-to-higher privilege boundary tests.

Authoritative sources

Complete CVE record and remediation plan

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