Is CVE-2026-21907 being actively exploited?

CVE-2026-21907 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2026-21907?

CVE-2026-21907 has a CVSS 3.1 base score of 5.9 (MEDIUM).

CVE-2026-21907

MEDIUM · CVSS 5.9EPSS 0.2%EU EUVD

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.

Key facts

CVSS score: 5.9 (v3.1)
Severity: MEDIUM
CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Weakness (CWE): CWE-327
EPSS score: 0.2% (9th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2026-2700)
Published: January 15, 2026
NVD last modified: June 17, 2026
Status: Analyzed

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2026-2700 in the EU Vulnerability Database. Last updated in EUVD on January 15, 2026.

View on the EU Vulnerability Database

Affected products

juniper / junos space
juniper / junos space
juniper / junos space
juniper / junos space
juniper / junos space

Certified products that may be affected

2 FIPS 140 or Common Criteria certified products, from automated matching by sec-certs.org.

Junos Space Network Management Platform, with or without Network Director and with or without Security Director in JA2500 - Juniper Networks, Inc. - FIPS 140 3816 - historical
Junos Space Network Management Platform, with or without Network Director and with or without Security Director in Virtual Appliance - Juniper Networks, Inc. - FIPS 140 3779 - historical

References

https://kb.juniper.net/JSA106006(Vendor Advisory)
https://supportportal.juniper.net/JSA106006(Vendor Advisory)

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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