Vulnerability in Juniper Junos

CVE-2026-33787

An Improper Check for Unusual or Exceptional Conditions vulnerability in the chassis control daemon (chassisd) of Juniper Networks Junos OS on SRX1500, SRX4100, SRX4200 and SRX4600 allows a local attacker with low privileges to cause a complete Denial of Service (DoS). When a specific 'show chassis' CLI command is executed, chassisd crashes and restarts which causes a momentary impact to all traffic until all modules are online again. This issue affects Junos OS on SRX1500, SRX4100, SRX4200 and SRX4600:  * 23.2 versions before 23.2R2-S6, * 23.4 versions before 23.4R2-S7 * 24.2 versions before 24.2R2-S2, * 24.4 versions before 24.4R2, * 25.2 versions before 25.2R1-S1, 25.2R2.

EPSS: 0.001 (0.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-33787?
CVE-2026-33787 is a medium-severity vulnerability in Juniper Junos, classified under Improper Check for Unusual or Exceptional Conditions. CVSS score: 5.5/10. Published 2026-04-09.
How severe is CVE-2026-33787?
Medium severity. CVSS v3 base score is 5.5 out of 10.