Vulnerability in Juniper Networks Junos OS (CVE-2026-33801)
Summary
Vulnerability in Juniper Networks Junos OS (CVE-2026-33801). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
An Improper Check for Unusual or Exceptional Conditions vulnerability in the routing protocol daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved allows an adjacent, unauthenticated attacker sending a specific BGP update over an established BGP session to cause a Denial-of-Service (DoS).
Upon receipt of a specifically malformed non-inet/inet6 unicast BGP update, an RPD crash and restart is triggered, which will cause a complete service outage until routing has reconverged. The rpd crash occurs before the update can be readvertised, so there is no downstream propagation.
This issue affects:
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Junos OS versions 25.2 before 25.2R2;
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Junos OS Evolved versions 25.2 before 25.2R2-EVO.
This issue doesn't affect Junos OS versions before 25.2R1 nor Junos OS Evolved versions before 25.2R1-EVO.
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-33801 has been found in Juniper Networks Junos OS.
Risk of unauthorized operations or information disclosure. CVSS score: 6.5/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Juniper Networks Junos OS CVE-2026-33801" on the vendor's site.
CVE-2026-33801 (Juniper Networks Junos OS) — CWE-754 / CVSS v3 6.5
Attack vector: adjacent-network / unauthenticated / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-754) exists in Juniper Networks Junos OS.
Check the vendor advisory for the affected versions of Juniper Networks Junos OS.
Severity: Medium (CVSS 6.5/10). Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Juniper Networks Junos OS を使っているサービスとバージョンを洗い出す。
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2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- patch sirt@juniper.net
- web nvd.nist.gov
- web github.com