What is the CVSS score of CVE-2021-40394?

CVE-2021-40394 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: 2.9%.

Is there a public PoC exploit available for CVE-2021-40394?

Yes, a public proof-of-concept exploit is available for CVE-2021-40394. Prioritise patching immediately. EPSS: 2.9%.

Gerbv CVE-2021-40394

CRITICAL

Out-of-bounds Write (CWE-787)

2021-12-22 talos-cna@cisco.com

Buffer Overflow RCE Memory Corruption Gerbv Debian Linux

9.8

CVSS 3.1 · NVD

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

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

CVE Published

Dec 22, 2021 - 19:15 nvd

CRITICAL 9.8

DescriptionNVD

An out-of-bounds write vulnerability exists in the RS-274X aperture macro variables handling functionality of Gerbv 2.7.0 and dev (commit b5f1eacd) and the forked version of Gerbv (commit 71493260). A specially-crafted gerber file can lead to code execution. An attacker can provide a malicious file to trigger this vulnerability.

AnalysisAI

An out-of-bounds write vulnerability exists in the RS-274X aperture macro variables handling functionality of Gerbv 2.7.0 and dev (commit b5f1eacd) and the forked version of Gerbv (commit 71493260). 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.

Technical ContextAI

This vulnerability is classified as Out-of-bounds Write (CWE-787), which allows attackers to write data beyond allocated buffer boundaries leading to code execution or crashes. An out-of-bounds write vulnerability exists in the RS-274X aperture macro variables handling functionality of Gerbv 2.7.0 and dev (commit b5f1eacd) and the forked version of Gerbv (commit 71493260). A specially-crafted gerber file can lead to code execution. An attacker can provide a malicious file to trigger this vulnerability. Affected products include: Gerbv Project Gerbv, Debian Debian Linux.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Validate write boundaries, use memory-safe languages, enable compiler protections (ASLR, stack canaries).