CWE-1320: Improper Protection for Outbound Error Messages and Alert Signals

Extended Description

Hardware sensors are used to detect whether a device is operating within design limits. The threshold values for these limits are set by hardware fuses or trusted software such as a BIOS. Modification of these limits may be protected by hardware mechanisms. When device sensors detect out of bound conditions, alert signals may be generated for remedial action, which may take the form of device shutdown or throttling. Warning signals that are not properly secured may be disabled or used to generate spurious alerts, causing degraded performance or denial-of-service (DoS). These alerts may be masked by untrusted software. Examples of these alerts involve thermal and power sensor alerts.

Code Examples & CVEs

Demonstrative Examples

Consider a platform design where a Digital-Thermal Sensor (DTS) is used to monitor temperature and compare that output against a threshold value. If the temperature output equals or exceeds the threshold value, the DTS unit sends an alert signal to the processor. The processor, upon getting the alert, input triggers system shutdown. The alert signal is handled as a General-Purpose-I/O (GPIO) pin in input mode.

Reprogramming the state of the GPIO pin allows malicious software to trigger spurious alerts or to set the alert pin to a zero value so that thermal sensor alerts are not received by the processor.

BadOther

The processor-GPIO controller exposes software-programmable controls that allow untrusted software to reprogram the state of the GPIO pin.

Reprogramming the state of the GPIO pin allows malicious software to trigger spurious alerts or to set the alert pin to a zero value so that thermal sensor alerts are not received by the processor.

GoodOther

The GPIO alert-signal pin is blocked from untrusted software access and is controlled only by trusted software, such as the System BIOS.

Source-backed guidance

Additional facts reviewed against primary or authoritative security sources.

Verify controls for CWE-1320 with SSDF evidence

Use NIST SSDF verification and vulnerability-response practices to detect CWE-1320, Improper Protection for Outbound Error Messages and Alert Signals, throughout the product lifecycle. Derive review questions, static or dynamic checks, and negative tests from the CWE's causal behavior; define the components and lifecycle stages each check covers; and retain findings with enough evidence to distinguish the root cause from symptoms and impacts. Track escapes and false negatives, then improve the verification plan after every confirmed occurrence.

NIST SP 800-218 Secure Software Development Framework — National Institute of Standards and Technology

Address Improper Protection for Outbound Error Messages and Alert Signals during Architecture and Design

MITRE associates mitigation with Architecture and Design; recorded impacts include DoS: Instability, DoS: Crash, Exit, or Restart, Reduce Reliability, and Unexpected State; the entry maps to CAPEC-1, and CAPEC-180. Use these source-defined anchors to turn CWE-1320 into implementation, review, and verification checks for the affected component.

CWE-1320: Improper Protection for Outbound Error Messages and Alert Signals — MITRE CWE

Triage CWE-1320 against known exploitation evidence

Use CISA's Known Exploited Vulnerabilities catalog to test whether a vulnerability mapped to CWE-1320, Improper Protection for Outbound Error Messages and Alert Signals, has evidence of exploitation in the wild. Confirm the CVE-to-CWE root-cause mapping independently before attaching the example, then capture the affected product, required action, and remediation deadline. A missing KEV match is not evidence that the weakness is unexploited, and a KEV entry must not be generalized to every occurrence of this CWE.

Known Exploited Vulnerabilities Catalog — Cybersecurity and Infrastructure Security Agency

Apply precise root-cause mapping to CWE-1320

Apply MITRE's full root-cause mapping guidance when using CWE-1320, Improper Protection for Outbound Error Messages and Alert Signals. Separate weakness language from attacker prerequisites and technical impact, check the entry's abstraction and vulnerability-mapping notes, and prefer the most specific Base or Variant supported by the evidence. Record the rejected alternatives and require an independent review before the mapping is used for remediation trends or program metrics.

CVE to CWE Root Cause Mapping Guidance — MITRE CWE

Validate CWE-1320 with root-cause mapping checks

Apply MITRE's root-cause mapping quick tips to CWE-1320, Improper Protection for Outbound Error Messages and Alert Signals. Confirm the finding describes the causal weakness rather than an impact or attack pattern, compare the abstraction and mapping notes with plausible alternatives, and have a second reviewer challenge the selection. Preserve the evidence and reasoning so recurring defects can be measured against one consistent identifier.

CVE to CWE Root Cause Mapping Quick Tips — MITRE CWE

Frequently Asked Questions

What is CWE-1320: Improper Protection for Outbound Error Messages and Alert Signals?+

CWE-1320: Improper Protection for Outbound Error Messages and Alert Signals is a Common Weakness Enumeration (CWE) entry maintained by MITRE. Untrusted agents can disable alerts about signal conditions exceeding limits or the response mechanism that handles such alerts. Hardware sensors are used to detect whether a device is operating within design limits. The threshold values for these limits are set by hardware fuses or trusted software such as a BIOS. Modification of these limits may be protected by hardware mechanisms. When device sensors detect out of bound conditions, alert signals may be generated for remedial action, which may take the form of device shutdown or throttling. Warning signals that are not properly secured may be disabled or used to generate spurious alerts, causing degraded performance or denial-of-service (DoS). These alerts may be masked by untrusted software. Examples of these alerts involve thermal and power sensor alerts.

What are the security consequences of Improper Protection for Outbound Error Messages and Alert Signals?+

If exploited, CWE-1320 (Improper Protection for Outbound Error Messages and Alert Signals) it can compromise Availability, leading to outcomes such as DoS: Instability, DoS: Crash, Exit, or Restart, Reduce Reliability and Unexpected State.

How do you prevent or mitigate Improper Protection for Outbound Error Messages and Alert Signals?+

Recommended mitigations for CWE-1320 include: Alert signals generated by critical events should be protected from access by untrusted agents. Only hardware or trusted firmware modules should be able to alter the alert configuration.

Which programming languages are affected by Improper Protection for Outbound Error Messages and Alert Signals?+

CWE-1320 commonly affects Not Language-Specific. Note that weaknesses are often language-agnostic patterns, so secure coding practices apply broadly.

What is the difference between a CWE and a CVE?+

A CWE (Common Weakness Enumeration) like CWE-1320 describes a category of software weakness — the underlying flaw type. A CVE (Common Vulnerabilities and Exposures) identifies a specific, real-world vulnerability in a particular product. In short, a CWE is the kind of mistake, and a CVE is an instance of that mistake being found in software.

CWE-1320: Improper Protection for Outbound Error Messages and Alert Signals

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