What is the CVSS score of CVE-2021-1104?

CVE-2021-1104 has a CVSS 3.1 base score of 9.8 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 1.7%.

Is there a public PoC exploit available for CVE-2021-1104?

Yes, a public proof-of-concept exploit is available for CVE-2021-1104. Prioritise patching immediately. EPSS: 1.7%.

Instruction Set Manual CVE-2021-1104

CRITICAL

Use of Uninitialized Resource (CWE-908)

2021-08-13 psirt@nvidia.com

Denial Of Service Information Disclosure Instruction Set Manual

9.8

CVSS 3.1 · NVD

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Vulnerability Assessment

Weakness	CWE CWE-908 ASVS 5.0 V15 - Secure Coding and Architecture Variable initialization
Impact	CVSS score of 9.8 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. Public proof-of-concept exploit code is available.
Exploit ScenarioDerived	A remote attacker could access uninitialized memory causing crashes or information disclosure by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability.

Act Now Prioritize within 24-48h. Why: CRITICAL severity + public POC available.

No patch listed yet 1.7% exploitation probability (EPSS)

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AnalysisAI

The RISC-V Instruction Set Manual contains a documented ambiguity for the Machine Trap Vector Base Address (MTVEC) register that may lead to a vulnerability due to the initial state of the register. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Initialize all variables, use compiler warnings for uninitialized access, use memory-safe languages.

Affects your stack

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Technical ContextAI · show details

This vulnerability is classified as Use of Uninitialized Resource (CWE-908), which allows attackers to access uninitialized memory causing crashes or information disclosure. The RISC-V Instruction Set Manual contains a documented ambiguity for the Machine Trap Vector Base Address (MTVEC) register that may lead to a vulnerability due to the initial state of the register not being defined, potentially leading to information disclosure, data tampering and denial of service. Affected products include: Risc-V Instruction Set Manual.

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Exploit and PoC references, threat intelligence from 22 sources

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Severity by source

NVD PRIMARY 9.8 CRITICAL

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

DescriptionNVD

The RISC-V Instruction Set Manual contains a documented ambiguity for the Machine Trap Vector Base Address (MTVEC) register that may lead to a vulnerability due to the initial state of the register not being defined, potentially leading to information disclosure, data tampering and denial of service.

Threat Intelligence Overview

EPSS Score

1.7%

Top 26% exploitable

Exploit

POC

Public exploit code exists

Data Quality

2 sources

Confidence: Low

NVD

CVE.org

EPSS

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue

Severity CRITICAL

CISA KEV No

Public POC Yes

EPSS 1.7%

Patch available No

Active threat No

Deciding rule

CRITICAL severity + public POC available

What every action level means

Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.

Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.

This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.

This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.

Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived

Scheduled

Exploitation· derived

Poc

System Exposure· derived

Open

Automatable· derived

Yes

Human Impact· derived

Medium

Priority Score

Low Medium High Critical

KEV: 0

EPSS: +2

CVSS: +49

PoC: +20

Weaponized: 0

Threat intel: 0

Gov advisory: 0

Attack Technique

Information Disclosure MEDIUM

Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.

Denial of Service MEDIUM

Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.