CVE-2026-21907

mediumpriority · track · 0OT risk · elevatedEPSS 0.002 · 10 %ileDEEUNLUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.20% (10th) EPSS

CVSS 5.9 · medium

Is it mine?

10 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · cert_bund · ncsc_nl

EPSS · scored 2026-10-27

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

Technical severity, 0–10. One row per scoring source.

8.2

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.6–8.2

v3.15.9mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · sirt@juniper.net USexploitability 2.2 · impact 3.6

v3.15.9mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:Nsecondary · NCSC-NL NL

v4.08.2highCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:L/SI:N/SA:N/AU:Y/RE:M/U:Greensecondary · ENISA EU

v4.08.2highCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:L/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:X/V:X/RE:M/U:Greensecondary · sirt@juniper.net US

v4.04.6mediumCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:L/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:X/V:X/RE:M/U:Greensecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-327USCWE-327US

affected products (10)

Products and version ranges known to be affected.

Juniper Junos Space <24.1R5all versionscert_bundDE
Juniper Junos Space< 24.1R5cert_bundDE
Juniper Networks Junos Space0 → 24.1R5enisa_euvdEU
Juniper Networks Junos OS≤ vers:unknown/*ncsc_nlNL
Juniper Networks Junos OS Evolved≤ vers:unknown/*ncsc_nlNL
Juniper Networks Junos Space≤ vers:unknown/*ncsc_nlNL
Juniper Networks Paragon Automation (Pathfinder, Planner, Insights)≤ vers:unknown/*ncsc_nlNL
Juniper Networks Spac≤ vers:unknown/*ncsc_nlNL
juniper junos space< 24.1nvdUScpe:2.3:a:juniper:junos_space:*:*:*:*:*:*:*:*
juniper junos space= 24.1nvdUScpe:2.3:a:juniper:junos_space:*:*:*:*:*:*:*:*

advisories (2)

Vendor and ecosystem advisories describing this.

NCSC-2026-0017Kwetsbaarheden verholpen in Juniper Networks JunOSNL2026-01-16csaf · ncsc_nlNL
Juniper heeft kwetsbaarheden verholpen in Junos OS (Specifiek voor SRX en MX Series apparaten).
WID-SEC-W-2026-0117Juniper Junos OS, Junos Space: Mehrere SchwachstellenDeutsch2026-01-14csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Juniper JUNOS und Juniper Junos Space ausnutzen, um falsche Informationen darzustellen, beliebigen Code mit Root-Rechten auszuführen, Daten zu manipulieren, vertrauliche Informationen offenzulegen und einen Denial-of-Service-Zustand zu verursachen.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund ncsc_nl nvd NVD CVE.org MITRE

published 2026-01-15modified 2026-06-17

references (8)

External citations — patches, advisories, analysis.

scry

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