CVE-2026-57025: Junos OS I2ald DoS via show I2-learning Command

Vulnerability Overview Vulnerability Name: 2026-07 Security Bulletin: Junos OS and Junos OS Evolved: EX Series, QFX Series, MX Series: A specific 'show I2-learning' command causes I2ald crash (CVE-2026-57025) Vulnerability Description: A vulnerability exists in the I2 library of Juniper Networks' Junos OS and Junos OS Evolved, where a pointer value exceeds its expected range. This allows a local low-privilege attacker to trigger a crash in I2ald by sending a specific 'show I2-learning' command, resulting in a denial of service (DoS). Affected Scope Affected Products: - Junos OS: - All versions prior to 23.2R2-S7 - 23.4 versions prior to 23.4R2-S7 - 24.2 versions prior to 24.2R2 - 24.4 versions prior to 24.4R1-S2 - Junos OS Evolved: - All versions prior to 23.2R2-S7-EVO - 23.4 versions prior to 23.4R2-S8-EVO - 24.2 versions prior to 24.2R2-EVO - 24.4 versions prior to 24.4R1-S3-EVO Affected Platforms: EX Series, QFX Series, MX Series Remediation Fixed Versions: - Junos OS: 23.2R2-S7, 23.4R2-S7, 24.2R2, 24.4R1-S2, 24.4R2, 25.1R1, and all subsequent versions - Junos OS Evolved: 23.2R2-S7-EVO, 23.4R2-S8-EVO, 24.2R2-EVO, 24.4R1-S3-EVO, 24.4R2-EVO, 25.1R1-EVO, and all subsequent versions Workarounds: - Use access control lists (ACLs) or firewall filters to restrict CLI access, allowing access only from trusted hosts and administrators. Additional Information CVSS Scores: - CVSS v3.1: 5.5 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H) - CVSS v4.0: 6.8 (CVSS:4.0/AV:L/AC:L/AT:L/PR:L/UI:N/V:N/V:H/VA:H/SC:N/SI:H/SA:H/RE:M) Related Documentation: - KB16413: Juniper Networks SIRT Quarterly Security Bulletin Publication Process - KB16765: In which releases are vulnerabilities fixed? - KB16446: Common Vulnerability Scoring System (CVSS) and Juniper's Security Advisories - Report a Security Vulnerability - How to Contact the Juniper Networks Security Incident Response Team Notes This vulnerability has been assigned CVE-2026-57025. Juniper SIRT has not found any evidence of malicious exploitation of this vulnerability. This issue was discovered during internal product security testing or research.

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CVE-2026-57025: Junos OS I2ald DoS via show I2-learning Command