Vulnerability in Juniper EX Series, QFX Series, MX Series (CVE-2026-57025)
Summary
Vulnerability in Juniper EX Series, QFX Series, MX Series (CVE-2026-57025). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
A Return of Pointer Value Outside of Expected Range vulnerability in the fileio library of Juniper Networks Junos OS and Junos OS Evolved allows a local, low-privilged attacker to cause a Denial-of-Service (DoS).
On EX Series, QFX Series and MX Series a low-privileged attacker issuing a specific 'show l2-learning' command will cause an l2ald crash which will lead to a temporary service impact for all layer 2 services until the process has automatically restarted.
This issue affects EX Series, QFX Series, MX Series:
Junos OS:
- all versions before 23.2R2-S7,
- 23.4 versions before 23.4R2-S7,
- 24.2 versions before 24.2R2,
- 24.4 versions before 24.4R1-S2.
Junos OS Evolved:
- all versions before 23.2R2-S7-EVO,
- 23.4 versions before 23.4R2-S8-EVO,
- 24.2 versions before 24.2R2-EVO,
- 24.4 versions before 24.4R1-S3-EVO.
Source: NIST National Vulnerability Database 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-2026-57025 has been found in Juniper EX Series, QFX Series, MX Series.
Risk of unauthorized operations or information disclosure. CVSS score: 5.5/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Juniper EX Series, QFX Series, MX Series CVE-2026-57025" on the vendor's site.
CVE-2026-57025 (Juniper EX Series, QFX Series, MX Series) — CWE-466 / CVSS v3 5.5
Attack vector: local / 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-466) exists in Juniper EX Series, QFX Series, MX Series.
Check the vendor advisory for the affected versions of Juniper EX Series, QFX Series, MX Series.
Severity: Medium (CVSS 5.5/10). 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
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Juniper EX Series, QFX Series, MX Series を使っているサービスとバージョンを洗い出す。
-
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