Junos OS and Junos OS Evolved: An attacker sending a specific genuine BGP packet causes a BGP reset
Key facts
- Attack vector
- Adjacent network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
Summary
An Improper Input Validation vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker, sending a specific genuine BGP packet in an already established BGP session to reset only that session causing a Denial of Service (DoS). An attacker repeatedly sending the packet will sustain the Denial of Service (DoS).This issue affects Junos OS: * 25.2 versions before 25.2R2 This issue does not affect Junos OS versions before 25.2R1. This issue affects Junos OS Evolved: * 25.2-EVO versions before 25.2R2-EVO This issue does not affect Junos OS Evolved versions before 25.2R1-EVO. eBGP and iBGP are affected. IPv4 and IPv6 are affected.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Juniper | Junos OS | 25.2 to before 25.2R2 | 25.2R2 | Patch available | CNA |
| Juniper | Junos OS Evolved | 25.2 to before 25.2R2-EVO | 25.2R2-EVO | Patch available | CNA |
- Junos OS VendorJuniper Affected 25.2 to before 25.2R2 Fixed in 25.2R2 Patch available CNA
- Junos OS Evolved VendorJuniper Affected 25.2 to before 25.2R2-EVO Fixed in 25.2R2-EVO Patch available CNA
CPE configurations NVD · 8
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:juniper:junos:25.2:-:*:*:*:*:*:* | 25.2 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:25.2:r1:*:*:*:*:*:* | 25.2 r1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:25.2:r1-s1:*:*:*:*:*:* | 25.2 r1-s1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos:25.2:r1-s2:*:*:*:*:*:* | 25.2 r1-s2 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos_os_evolved:25.2:-:*:*:*:*:*:* | 25.2 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos_os_evolved:25.2:r1:*:*:*:*:*:* | 25.2 r1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos_os_evolved:25.2:r1-s1:*:*:*:*:*:* | 25.2 r1-s1 | Vulnerable | Juniper |
| cpe:2.3:o:juniper:junos_os_evolved:25.2:r1-s2:*:*:*:*:*:* | 25.2 r1-s2 | Vulnerable | Juniper |
- cpe:2.3:o:juniper:junos:25.2:-:*:*:*:*:*:* Versions 25.2 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:25.2:r1:*:*:*:*:*:* Versions 25.2 r1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:25.2:r1-s1:*:*:*:*:*:* Versions 25.2 r1-s1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos:25.2:r1-s2:*:*:*:*:*:* Versions 25.2 r1-s2 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos_os_evolved:25.2:-:*:*:*:*:*:* Versions 25.2 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos_os_evolved:25.2:r1:*:*:*:*:*:* Versions 25.2 r1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos_os_evolved:25.2:r1-s1:*:*:*:*:*:* Versions 25.2 r1-s1 Vulnerable ·Juniper
- cpe:2.3:o:juniper:junos_os_evolved:25.2:r1-s2:*:*:*:*:*:* Versions 25.2 r1-s2 Vulnerable ·Juniper
Remediation
- Fix · CNA Junos OS (Juniper Networks) Fixed in 25.2R2
- Fix · CNA Junos OS Evolved (Juniper Networks) Fixed in 25.2R2-EVO
Timeline
- 2026-10-02 Threatist record created from CVE-2026-33797
- 2026-10-03 Alias added: GHSA-3rpc-j6fw-646r
References
More Juniper Junos vulnerabilities
- TI-2023-18638 Junos OS: EX and SRX Series: A PHP vulnerability in J-Web allows an unauthenticated to… KEVCVSS 3.1CRITICAL 9.8
- TI-2020-01585 Out of Cycle Security Advisory: Junos OS: Security vulnerability in J-Web and web based (HTTP/HTTPS) services KEVCVSS 3.1CRITICAL 9.8
- TI-2015-04610 Assertion failure in ISC BIND named via TKEY queries KEVCVSS 3.1HIGH 7.5
- TI-2025-15550 Junos OS: An local attacker with shell access can execute arbitrary code KEVCVSS 4.0MEDIUM 6.7
- TI-2023-18644 Junos OS: SRX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload and download arbitrary files KEVCVSS 3.1MEDIUM 5.3
- TI-2023-18640 Junos OS: EX Series: A vulnerability in J-Web allows an unauthenticated attacker to upload arbitrary files KEVCVSS 3.1MEDIUM 5.3
Sources
- CVE-2026-33797 · CVE Program
- CVE-2026-33797 · NVD
- FIRST EPSS
- GHSA-3rpc-j6fw-646r · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences