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
https://supportportal.juniper.net/JSA106006

Configurations

No configuration.

History

15 Jan 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-15 21:16

Updated : 2026-01-16 15:55

NVD link : CVE-2026-21907

Mitre link : CVE-2026-21907

CVE.ORG link : CVE-2026-21907

JSON object : View

Products Affected

No product.

CWE

CWE-327

Use of a Broken or Risky Cryptographic Algorithm

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