PHP2Shell : See if you’re affected with a free external attack surface scan. Click Here > 

Back
New CVE Detected

CVE-2026-33789 – Stack-based Buffer Overflow (DoS / Potential Root RCE) – Juniper Junos OS and Junos

Be the first to know when new zero-days emerge:

Subscribe to Email Alerts
Subscribe to RSS Feed

Summary

CVE-2026-33789 is a critical stack-based buffer overflow (CWE-121) in the routing protocol daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved. An unauthenticated BGP peer can cause a denial of service and potentially root-level command execution when the BGP Monitoring Protocol (BMP) is active. The CVSS v3.1 base score is 9.8 (Critical).

Technical details

  • Root cause: stack-based buffer overflow in the routing protocol daemon (rpd).
  • Trigger conditions: BGP Monitoring Protocol (BMP) must be active; the issue is triggered by a crafted BGP route update.
  • Attack vector: network, from an unauthenticated BGP peer; no user interaction required.
  • Impact: denial of service and potential root-level command execution.
  • The CVE record does not indicate that exploitation in the wild has been reported, and no public exploit was found during research.

Affected software

Junos OS

  • All versions before 23.2R2-S7.7
  • 23.4 versions before 23.4R2-S8.13
  • 24.2 versions before 24.2R2-S5.5
  • 24.4 versions before 24.4R2-S5
  • 25.2 versions before 25.2R2-S2
  • 25.4 versions before 25.4R1-S3
  • 26.2 versions before 26.2R1-S2

Junos OS Evolved

  • Corresponding -EVO releases of the branches above, plus the 23.4X100, 25.2X100 and 25.4X300 branches (see Juniper advisory JSA112187 for exact fixed builds).

Severity

  • CVSS v3.1 base score: 9.8 (Critical)
  • Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
  • CVSS v4.0 score: 9.2 (Critical)

Mitigation and recommended actions

  • Immediate: upgrade to a fixed release: 23.2R2-S7.7, 23.4R2-S8.13, 24.2R2-S5.5, 24.4R2-S5, 25.2R2-S2, 25.4R1-S3, 25.4R2, 26.2R1-S2, or later. For Junos OS Evolved, use the corresponding fixed builds listed in JSA112187.
  • Workarounds if patching is not immediately possible (per the CVE record): disable BMP functionality and avoid configuring family inet flow.
  • Review Juniper advisory JSA112187 for full details.

References

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report

How IONIX’s External Exposure Management Platform Detects and Validates
Zero-Days to Shrink MTTR

1

Map your entire attack surface (continously)

IONIX uses multi-factor discovery methods, including DNS analysis, certificate mapping, metadata inspection, and more, to automatically map every internet-facing asset across your environment. This includes cloud instances, third-party platforms, shadow IT, and even forgotten infrastructure that traditional tools miss.

2

Monitor for new CVEs

Dozens of threat intel feeds using agentic technology are continuously analyzed to detect the appearance of proof-of-concept code, exploit kits, and indicators of active targeting. IONIX goes further by applying AI to proactively evaluate whether emerging vulnerabilities are likely to be exploited, even before PoCs go public.

3

Identify Potential External Exposures

Not all CVEs matter. IONIX filters vulnerabilities by asking attacker-centric questions: Can it be reached from the internet? Does it require authentication? Is it being exploited in the wild? This dramatically reduces noise and focuses teams on threats that can actually be weaponized.

4

Create Safe, Scalable Exploit Validations

IONIX transforms real-world PoCs into safe, non-intrusive test payloads that can be run in production environments without disruption. These simulations are precisely targeted to the systems that are vulnerable, ensuring rapid validation without unnecessary load.

5

Execute Exploit Validations

By combining context about software stack, versioning, exposure status, and reachability, IONIX ensures that only the right payloads are executed against the right assets, maximizing efficiency and minimizing risk.

6

Drive Fast and Actionable Remediation

Results are routed through integrations with ticketing, SOAR, and SIEM tools. Issues are written in plain language, bundled into remediation clusters, and prioritized based on asset criticality, exploitability, and blast radius. This shortens mean time to remediation (MTTR) and empowers teams to act with confidence.

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report
Close

Subscribe to Threat Center RSS

Copy/paste the link below into your preferred RSS reader or follow these instructions to subscribe to Slack alerts.

Open RSS feedSlack setup instructions

Close

Get Real-Time CVE Alerts to Your Email

Be the first to know when new zero-days emerge