Junos OS Evolved SNMP firewall-counter query enables denial of service
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-617.
Summary
A Reachable Assertion flaw (CWE-617) in fwstatsd of Juniper Networks Junos OS Evolved lets an authenticated network attacker cause a denial of service with an SNMP firewall-counter MIB query. The attack works when at least one firewall counter is configured. The CVSS 4.0 base score is 8.7 (HIGH). CISA SSVC rates the issue as automatable with partial technical impact and exploitation as none, and it is not listed in CISA KEV.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Description from the CNA
A Reachable Assertion vulnerability in fwstatsd of Juniper Networks Junos OS Evolved allows an authenticated network attacker to cause a denial of service via an SNMP firewall-counter MIB query when at least one firewall counter is configured.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- 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 Evolved | before 23.2R2-S7.7-EVO; 23.4 to before 23.4R2-S8.11-EVO; 24.2 to before 24.2R2-S5.6-EVO; 24.4 to before 24.4R2-S5-EVO; 25.2 to before 25.2R2-S2-EVO; 25.4 to before 25.4R1-S3-EVO; 26.2 to before 26.2R1-S2-EVO; 23.4X100; 25.2X100 to before 25.2X100-D35-EVO; 25.4X300 to before 25.4X300-D40-EVO | 23.2R2-S7.7-EVO, 23.4R2-S8.11-EVO, 24.2R2-S5.6-EVO, 24.4R2-S5-EVO, 25.2R2-S2-EVO, 25.4R1-S3-EVO, 26.2R1-S2-EVO, 25.2X100-D35-EVO, 25.4X300-D40-EVO | Patch available | CNA |
- Junos OS Evolved VendorJuniper Affected before 23.2R2-S7.7-EVO; 23.4 to before 23.4R2-S8.11-EVO; 24.2 to before 24.2R2-S5.6-EVO; 24.4 to before 24.4R2-S5-EVO; 25.2 to before 25.2R2-S2-EVO; 25.4 to before 25.4R1-S3-EVO; 26.2 to before 26.2R1-S2-EVO; 23.4X100; 25.2X100 to before 25.2X100-D35-EVO; 25.4X300 to before 25.4X300-D40-EVO Fixed in 23.2R2-S7.7-EVO, 23.4R2-S8.11-EVO, 24.2R2-S5.6-EVO, 24.4R2-S5-EVO, 25.2R2-S2-EVO, 25.4R1-S3-EVO, 26.2R1-S2-EVO, 25.2X100-D35-EVO, 25.4X300-D40-EVO Patch available CNA
Remediation
Upgrade Junos OS Evolved to a fixed release for your train: 23.2R2-S7.7-EVO, 23.4R2-S8.11-EVO, 24.2R2-S5.6-EVO, 24.4R2-S5-EVO, 25.2R2-S2-EVO, 25.4R1-S3-EVO, 26.2R1-S2-EVO, 25.2X100-D35-EVO or 25.4X300-D40-EVO.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
- Fix · CNA Junos OS Evolved (Juniper Networks) Fixed in 23.2R2-S7.7-EVO, 23.4R2-S8.11-EVO, 24.2R2-S5.6-EVO, 24.4R2-S5-EVO, 25.2R2-S2-EVO, 25.4R1-S3-EVO, 26.2R1-S2-EVO, 25.2X100-D35-EVO, 25.4X300-D40-EVO
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Advisory ·
Juniper Networks Junos OS Evolved — supportportal.juniper.net/JSA112250
12 records Highest priority Priority MEDIUM 8 MEDIUM, 4 LOW
Other records, highest priority first
- TI-2026-74245 OS command injection in Junos OS Evolved TACACS+ allows root commandsPriority MEDIUM 52
- TI-2026-74199 OS command injection in Junos OS Evolved zero-touch provisioningPriority MEDIUM 49
- TI-2026-74281 Stack buffer overflow in Junos OS Evolved kernel causes kernel panicPriority MEDIUM 47
Timeline
- 2026-10-15 Threatist record created from CVE-2026-102023
- 2026-10-16 Priority changed: MEDIUM → LOW
- 2026-10-16 CISA SSVC decision points changed
- 2026-10-16 Priority changed: LOW → MEDIUM
References
More Juniper 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-2015-06436 Juniper ScreenOS 6.2.0r15 through 6.2.0r18, 6.3.0r12 before 6.3.0r12b, 6.3.0r13 before… KEVCVSS 3.1CRITICAL 9.8
- TI-2022-20885 Apache Commons Text prior to 1.10.0 allows RCE when applied to untrusted input due to insecure interpolation defaults CVSS 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
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences