Vulnerability in Juniper Junos

CVE-2026-33779

An Improper Following of a Certificate's Chain of Trust vulnerability in J-Web of Juniper Networks Junos OS on SRX Series allows a PITM to intercept the communication of the device and get access to confidential information and potentially modify it. When an SRX device is provisioned to connect to Security Director (SD) cloud, it doesn't perform sufficient verification of the received server certificate. This allows a PITM to intercept the communication between the SRX and SD cloud and access credentials and other sensitive information. This issue affects Junos OS: * all versions before 22.4R3-S9, * 23.2 versions before 23.2R2-S6, * 23.4 versions before 23.4R2-S7, * 24.2 versions before 24.2R2-S3, * 24.4 versions before 24.4R2-S2, * 25.2 versions before 25.2R1-S2, 25.2R2.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N.

EPSS exploit prediction

EPSS: 0.002 (7.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 8th percentile — 7.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-33779: held from 0.001 to 0.002.

EPSS over last 30 days · oldest: 0.001 · newest: 0.002 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-33779?
CVE-2026-33779 is a medium-severity vulnerability in Juniper Junos, classified under Improper Following of a Certificate's Chain of Trust. CVSS score: 6.5/10. Published 2026-04-09.
How severe is CVE-2026-33779?
Medium severity. CVSS v3 base score is 6.5 out of 10.