CVE intelligence and bounded remediation

CVE-2020-35488 — Nxlog Nxlog security vulnerability

High CVSS 7.5

The fileop module of the NXLog service in NXLog Community Edition 2.10.2150 allows remote attackers to cause a denial of service (daemon crash) via a crafted Syslog payload to the Syslog service. This attack requires a specific configuration. Also, the name of the directory created must use a Syslog field. (For example, on Linux it is not possible to create a .. directory. On Windows, it is not possible to create a CON directory.)

Severity
High
CVSS
7.5 (3.1)
Published
2021-01-05
CISA KEV
Not currently listed
Ecosystem
windows/system
Weaknesses
CWE-502

Affected products

  • nxlog / nxlog

Matched remediation archetype

Unsafe deserialization and object reconstruction

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

Check exposure

  • Inventory serialization formats accepted from requests, queues, caches, files, cookies, and cross-service messages.
  • Trace whether untrusted input can select classes, types, callbacks, constructors, or object hooks during decoding.
  • Identify signing, schema validation, trust-boundary, and compatibility settings for each decoder.

Remediate safely

  • Replace native object deserialization with a data-only format and explicit schema validation.
  • If replacement is not immediate, use a safe decoder with a minimal type allowlist and disable polymorphic or executable hooks.
  • Update the affected library and add inert tests for unknown types, extra fields, malformed nesting, and unsigned data.

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.