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TI-2026-74198 Aliases CVE-2026-101966

Format string flaw in Junos OS Evolved enables telemetry DoS

Priority MEDIUM 44CWE-134Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
Low · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

Juniper Networks Junos OS Evolved is affected from 23.4X100 and in the listed earlier branches. A format string flaw (CWE-134) in the jti-dialoutd daemon is triggered by a crafted analytics sensor resource. An authenticated network attacker can submit that resource through the gNMI listener to cause persistent telemetry dial-out denial of service.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

A Use of Externally-Controlled Format String vulnerability in the jti-dialoutd of Juniper Networks Junos OS Evolved allows an authenticated network attacker to cause persistent telemetry dial-out denial of service via a crafted analytics sensor resource submitted through gNMI listener.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00427 37th percentileScored 2026-11-07
Fix Fixed Junos OS Evolved (Juniper Networks): 25.4R1-S3-EVO, 26.2R1-S2-EVO, 25.2X100-D35-EVO +1

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

VendorProductAffected versionsFixed inStatusSource
JuniperJunos OS Evolved25.4 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-EVO25.4R1-S3-EVO, 26.2R1-S2-EVO, 25.2X100-D35-EVO, 25.4X300-D40-EVOPatch availableCNA
  • Junos OS Evolved VendorJuniper Affected 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 25.4R1-S3-EVO, 26.2R1-S2-EVO, 25.2X100-D35-EVO, 25.4X300-D40-EVO Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:juniper:junos_os_evolved:*:*:*:*:*:*:*:*——Juniper
  • cpe:2.3:o:juniper:junos_os_evolved:*:*:*:*:*:*:*:* Versions — — ·Juniper

Remediation

Upgrade to 25.4R1-S3-EVO, 26.2R1-S2-EVO, 25.2X100-D35-EVO or 25.4X300-D40-EVO, depending on the branch in use. The sources list no fixed version for Junos OS Evolved 23.4X100.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA Junos OS Evolved (Juniper Networks) Fixed in 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
    Show all 12 records → Advisory →

Timeline

  1. 2026-10-15 Threatist record created from CVE-2026-101966

References

Advisory 1

  • 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
See all 1284 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences