What is the CVSS score of CVE-2021-21887?

CVE-2021-21887 has a CVSS 3.1 base score of 9.1 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H. EPSS exploitation probability: 3.0%.

Is there a public PoC exploit available for CVE-2021-21887?

Yes, a public proof-of-concept exploit is available for CVE-2021-21887. Prioritise patching immediately. EPSS: 3.0%.

Premierwave 2050 Firmware CVE-2021-21887

CRITICAL

Stack-based Buffer Overflow (CWE-121)

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

Buffer Overflow RCE Stack Overflow Premierwave 2050 Firmware

9.1

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

9.1 CRITICAL

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

High

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

CVE Published

Dec 22, 2021 - 19:15 nvd

CRITICAL 9.1

DescriptionNVD

A stack-based buffer overflow vulnerability exists in the Web Manager SslGenerateCSR functionality of Lantronix PremierWave 2050 8.9.0.0R4 (in QEMU). A specially crafted HTTP request can lead to remote code execution. An attacker can make an authenticated HTTP request to trigger this vulnerability.

AnalysisAI

A stack-based buffer overflow vulnerability exists in the Web Manager SslGenerateCSR functionality of Lantronix PremierWave 2050 8.9.0.0R4 (in QEMU). Rated critical severity (CVSS 9.1), this vulnerability is remotely exploitable, low attack complexity. Public exploit code available and no vendor patch available.

Technical ContextAI

This vulnerability is classified under CWE-121. A stack-based buffer overflow vulnerability exists in the Web Manager SslGenerateCSR functionality of Lantronix PremierWave 2050 8.9.0.0R4 (in QEMU). A specially crafted HTTP request can lead to remote code execution. An attacker can make an authenticated HTTP request to trigger this vulnerability. Affected products include: Lantronix Premierwave 2050 Firmware.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.