CVE intelligence and bounded remediation

CVE-2021-21723 — Some ZTE products have a DoS vulnerability

High CVSS 7.5

Some ZTE products have a DoS vulnerability. Due to the improper handling of memory release in some specific scenarios, a remote attacker can trigger the vulnerability by performing a series of operations, resulting in memory leak, which may eventually lead to device denial of service. This affects: ZXR10 9904, ZXR10 9908, ZXR10 9916, ZXR10 9904-S, ZXR10 9908-S; all versions up to V1.01.10.B12.

Severity
High
CVSS
7.5 (3.1)
Published
2021-01-26
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-401

Affected products

  • zte / zxr10_9904_firmware
  • zte / zxr10_9908_firmware
  • zte / zxr10_9916_firmware
  • zte / zxr10_9904-s_firmware
  • zte / zxr10_9908-s_firmware

Matched remediation archetype

Resource exhaustion and denial of service

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

Check exposure

  • Identify attacker-influenced work factors including input size, nesting, compression, fan-out, regex cost, allocation, recursion, retries, and connection lifetime.
  • Map per-request and shared CPU, memory, disk, descriptor, thread, queue, and downstream-service limits.
  • Determine whether authentication, tenancy, quotas, and rate controls apply before expensive processing begins.

Remediate safely

  • Bound input size, nesting, expansion, work, concurrency, queue depth, retries, and execution time before resource-intensive processing.
  • Release resources on every success, error, cancellation, and timeout path and use backpressure instead of unbounded buffering.
  • Update affected components and add small deterministic tests that assert resource ceilings rather than exhausting a host.

Authoritative sources

Complete CVE record and remediation plan

The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.