CVE intelligence and bounded remediation

CVE-2023-29487 — Heimdalsecurity Thor security vulnerability

Critical CVSS 9.1

An issue was discovered in Heimdal Thor agent versions 3.4.2 and before on Windows and 2.6.9 and before on macOS, allows attackers to cause a denial of service (DoS) via the Threat To Process Correlation threat prevention module. NOTE: Heimdal asserts this is not a valid vulnerability. Their DNS Security for Endpoint solution includes an optional feature to provide extra information on the originating process that made a DNS request. The lack of process identification in DNS logs is therefore falsely categorized as a DoS issue.

Severity
Critical
CVSS
9.1 (3.1)
Published
2023-12-21
CISA KEV
Not currently listed
Ecosystem
windows/system
Weaknesses
CWE-1333

Affected products

  • heimdalsecurity / thor

Showing 1 representative product identities from 2 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

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

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