OpenSSL TLS server denial-of-service (CVE-2021-3449)

Advisory ID CVE Number Date discovered Severity Advisory revision
STORM-2021-009 CVE-2021-3449 03/25/2021 medium v1

Vulnerability details

An OpenSSL TLS server may crash if sent a maliciously crafted renegotiation ClientHello message.

Impacted products

Stormshield Network Security medium SNS is impacted


Version Date Description
v1  05/27/2021 Initial release


Stormshield Network Security

CVSS v3.1 Overall Score: 5.1      


Impacted version

A bug in OpenSSL’s secure renegociation system could lead to a remote denial of service on multiple services running on SNS.

  • SNS 4.2.1

Workaround solution


There is no workaround.

The 4.2.2 update fixes this vulnerability.

Attack Vector Attack Complexity Privileges Required User Interaction Scope Confidentiality Impact Integrity Impact Availability impact
Adjacent Network Low None None Changed None None Low
CVSS Base score: 4.7 CVSS Vector: (AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L)
Exploit Code Maturity Remediation Level Report Confidence
Proof of concept code Official fix Confirmed
CVSS Temporal score: 4.2 CVSS Vector: (AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L/E:P/RL:O/RC:C)
Confidentiality Requirement Integrity Requirement Availability Requirement
High High High
CVSS Environmental score: 5.1 CVSS Vector: (AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L/E:P/RL:O/RC:C/CR:H/IR:H/AR:H/MAV:X/MAC:X/MPR:X/MUI:X/MS:X/MC:X/MI:X/MA:X)