CVE-2026-21907

A Use of a Broken or Risky Cryptographic Algorithm vulnerability in the TLS/SSL server of Juniper Networks Junos Space allows the use of static key ciphers (ssl-static-key-ciphers), reducing the confidentiality of on-path traffic communicated across the connection. These ciphers also do not support Perfect Forward Secrecy (PFS), affecting the long-term confidentiality of encrypted communications.This issue affects all versions of Junos Space before 24.1R5.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://kb.juniper.net/JSA106006	Vendor Advisory
https://supportportal.juniper.net/JSA106006	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:juniper:junos_space::::::::
	cpe:2.3:a:juniper:junos_space:24.1:r1::::::
	cpe:2.3:a:juniper:junos_space:24.1:r2::::::
	cpe:2.3:a:juniper:junos_space:24.1:r3::::::
	cpe:2.3:a:juniper:junos_space:24.1:r4::::::

History

23 Jan 2026, 20:02

Type	Values Removed	Values Added
References	~~() https://kb.juniper.net/JSA106006 -~~	() https://kb.juniper.net/JSA106006 - Vendor Advisory
References	~~() https://supportportal.juniper.net/JSA106006 -~~	() https://supportportal.juniper.net/JSA106006 - Vendor Advisory
First Time		Juniper Juniper junos Space
CPE		cpe:2.3:a:juniper:junos_space:24.1:r3:::::: cpe:2.3:a:juniper:junos_space:24.1:r1:::::: cpe:2.3:a:juniper:junos_space:24.1:r4:::::: cpe:2.3:a:juniper:junos_space:::::::: cpe:2.3:a:juniper:junos_space:24.1:r2::::::

15 Jan 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-15 21:16

Updated : 2026-01-23 20:02

NVD link : CVE-2026-21907

Mitre link : CVE-2026-21907

CVE.ORG link : CVE-2026-21907

JSON object : View

Products Affected

juniper

junos_space

CWE

CWE-327

Use of a Broken or Risky Cryptographic Algorithm

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