CVE-2026-33783Network attack vector

Persistent service interruption via oversized Originator ASN

Published Apr 9, 2026 · Updated Apr 9, 2026

Incorrect-argument function calls in Juniper Networks Junos OS Evolved on PTX Series allow remote authenticated users to cause a persistent crash. The sensor interface mishandles a 32-bit Originator ASN greater than 65,535 while gRPC monitors PCEP-provisioned colored SRTE tunnels, causing evo-aftmand to exit without restarting. Low-privileged network access, PCEP-provisioned tunnels, and active gRPC monitoring are required; recovery requires a manual system restart.

CVSS severity7.1
High
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Incorrect-argument function calls in Juniper Networks Junos OS Evolved on PTX Series allow remote authenticated users to cause a persistent crash. The sensor interface mishandles a 32-bit Originator ASN greater than 65,535 while gRPC monitors PCEP-provisioned colored SRTE tunnels, causing evo-aftmand to exit without restarting. Low-privileged network access, PCEP-provisioned tunnels, and active gRPC monitoring are required; recovery requires a manual system restart.

The record

CVE
CVE-2026-33783
Published
Apr 9, 2026
Updated
Apr 9, 2026
Vendor
Juniper Networks
Product
Junos OS Evolved
Classifications
CWE-686, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 9, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 9, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <22.4R3-S9-EVO
  2. Affected versionversion=23.2 <23.2R2-S6-EVO
  3. Affected versionversion=23.4 <23.4R2-S7-EVO
  4. Affected versionversion=24.2 <24.2R2-S4-EVO
  5. Affected versionversion=24.4 <24.4R2-S2-EVO
  6. Affected versionversion=25.2 <25.2R1-S2-EVO, 25.2R2-EVO

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Juniper Networks · Junos OS Evolvedversion=0 <22.4R3-S9-EVO; version=23.2 <23.2R2-S6-EVO; version=23.4 <23.4R2-S7-EVO; version=24.2 <24.2R2-S4-EVO; version=24.4 <24.4R2-S2-EVO; version=25.2 <25.2R1-S2-EVO, 25.2R2-EVO

Published CVSS scores

6.5Juniper Networks, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
7.1Juniper Networks, Inc.CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-686Function Call With Incorrect Argument Type
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo