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Response snapshot Oct 28, 2026, 18:56 UTC

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VulnerabilityCVE-2026-103401

An Improper Link Resolution Before File Access ('Link Following') vulnerability in the unauthenticated web server handlers in Juniper Networks Session Smart Router and Session...

An Improper Link Resolution Before File Access ('Link Following') vulnerability in the unauthenticated web server handlers in Juniper Networks Session Smart Router and Session Smart Conductor allows a local unprivileged user to overwrite arbitrary files as root via unauthenticated API endpoints.

At a glance

Exploited
Not known
Severity
8.8 High (CVSS 3.1)
Chance of exploitation
Not estimated
Sources
1 source

What to do

Check the vendor advisory for affected versions and fixes.

Read NVD CVE-2026-103401 (opens a new tab)

What happened

An Improper Link Resolution Before File Access ('Link Following') vulnerability in the unauthenticated web server handlers in Juniper Networks Session Smart Router and Session Smart Conductor allows a local unprivileged user to overwrite arbitrary files as root via unauthenticated API endpoints.

This vulnerability can be exploited on Mist-managed routers and on unmanaged Routers that have not yet been onboarded to a Conductor. Routers already managed by Conductor are not affected.

Scores and how they were measured

CVSS base severity

8.8

Version 3.1As of

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Measurement source (opens a new tab)

How bad it is if exploited. Not a prediction of exploitation or proof you are exposed.

EPSS probability

Not available

A model's estimate of exploitation in the next 30 days, not certainty or your own risk.

Related technology

Sources

  1. Primary source

    NVD CVE-2026-103401 (opens a new tab)

    NVD record: description, CVSS (the CNA score is preferred), affected products, and publication date. Not evidence of exploitation.

    Published Checked

  2. Primary source

    NVD CVE API 2.0 (opens a new tab)

    The NVD API page that supplied this CVE record.

    Published Date not suppliedChecked

  3. Primary source

    NVD CVE API 2.0 (opens a new tab)

    The NVD API page that supplied this CVE record.

    Published Date not suppliedChecked

  4. Primary source

    NVD CVE API 2.0 (opens a new tab)

    The NVD API page that supplied this CVE record.

    Published Date not suppliedChecked

Cite this record

For factual claims, cite the primary sources above; cite KEVWire for its compilation, dates, and classifications.

APA

KEVWire. (2026, October 28). An Improper Link Resolution Before File Access ('Link Following') vulnerability in the unauthenticated web server handlers in Juniper Networks Session Smart Router and Session... (CVE-2026-103401). https://kevwire.com/record/CVE-2026-103401

MLA

"An Improper Link Resolution Before File Access ('Link Following') vulnerability in the unauthenticated web server handlers in Juniper Networks Session Smart Router and Session... (CVE-2026-103401)." KEVWire, 28 Oct. 2026, kevwire.com/record/CVE-2026-103401.

Chicago

KEVWire. "An Improper Link Resolution Before File Access ('Link Following') vulnerability in the unauthenticated web server handlers in Juniper Networks Session Smart Router and Session... (CVE-2026-103401)." Last modified October 28, 2026. https://kevwire.com/record/CVE-2026-103401.

Evidence summary (plain text)

An Improper Link Resolution Before File Access ('Link Following') vulnerability in the unauthenticated web server handlers in Juniper Networks Session Smart Router and Session... (Oct 28, 2026).
An Improper Link Resolution Before File Access ('Link Following') vulnerability in the unauthenticated web server handlers in Juniper Networks Session Smart Router and Session Smart Conductor allows a local unprivileged user to overwrite arbitrary files as root via unauthenticated API endpoints.

This vulnerability can be exploited on Mist-managed routers and on unmanaged Routers that have not yet been onboarded to a Conductor. Routers already managed by Conductor are not affected.
CVSS 8.8 (version 3.1; evidence as of Oct 28, 2026; https://nvd.nist.gov/vuln/detail/CVE-2026-103401).
Sources:
NVD CVE-2026-103401: https://nvd.nist.gov/vuln/detail/CVE-2026-103401
NVD CVE API 2.0: https://services.nvd.nist.gov/rest/json/cves/2.0?lastModStartDate=2026-10-28T17:16:02.058Z&lastModEndDate=2026-10-28T18:55:58.318Z&resultsPerPage=500&startIndex=0
NVD CVE API 2.0: https://services.nvd.nist.gov/rest/json/cves/2.0?lastModStartDate=2026-10-28T16:40:59.949Z&lastModEndDate=2026-10-28T18:15:56.570Z&resultsPerPage=500&startIndex=0
NVD CVE API 2.0: https://services.nvd.nist.gov/rest/json/cves/2.0?lastModStartDate=2026-10-28T16:11:06.450Z&lastModEndDate=2026-10-28T17:40:58.118Z&resultsPerPage=500&startIndex=0
Record ID: CVE-2026-103401.
Record origin: Ingested record.
AI evidence: Not assessed.
Known exploitation: Not assessed.
Zero-day status: Not assessed. KEV membership alone does not establish zero-day status.
About this data

This record was ingested from a data source. Retrieved: Oct 28, 2026, 18:55 UTC. Ingestion is not an independent editorial investigation.

NVD status: Awaiting Analysis. Publication in the NVD is not evidence of exploitation.

A CISA KEV listing documents known exploitation, not necessarily a zero-day; absence from the catalog does not prove a vulnerability has never been exploited.

Technology tags indicate possible relevance, not verified exposure. Confirm the affected product, version, and configuration against your own inventory; KEVWire does not scan your systems.

A personal reading checklist on this device, not verified remediation.

Record JSON

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Record details

Record detail