8.2

CVE-2026-21907: juniper networks junos space

CVSS: 8.2v4.0HighAnalyzed
Published 15-01-2026Last modified 15-01-2026
Open JSON

Vulnerability summary

CVE-2026-21907 is a high (CVSS 8.2) vulnerability in juniper networks junos space. EPSS estimates a 0.20% chance of exploitation in the next 30 days, higher than 9.4% of scored vulnerabilities.

Overall risk
33/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.2/10
010
High · v4.0 (CVE.org)
EPSS score
0.20%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 15-01-2026
    PublishedVulnerability first disclosed.
  2. 15-01-2026
    Last modifiedVulnerability information updated.

Description

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 metrics

4 scores · 2 sources · 2 versions

EPSS trend

Probability

0.20%

Chance of exploitation in the next 30 days

Percentile

9%

Versus all other CVEs

30-day change

0.00 pp

From 0.20% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.20%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Juniper1 product
  • junos_space< 24.1 | 24.1:r1 | 24.1:r2 | 24.1:r3 | 24.1:r4
Juniper networks1 product

2 vendors · 2 products

References

2 links