Live Exposure Defense: From CVE to Confirmed Exposure in 12 Hours – See more

Back
New CVE Detected

CVE-2026-75604 – Unauthenticated RCE via Cache Path Traversal – Next.js 13.4–15.5.23 and 16.0–16.3.2

Be the first to know when new zero-days emerge:

Subscribe to Email Alerts
Subscribe to RSS Feed

Summary

CVE-2026-75604 is a critical path traversal vulnerability (CWE-22) in Next.js that affects applications hosted on Windows filesystems. Next.js does not consistently escape backslashes in route segments before constructing incremental-cache paths, which can let an unauthenticated network attacker escape the intended cache directory, access sensitive build data such as encryption keys, and ultimately achieve remote code execution.

Technical details

  • Root cause: backslashes in route segments are not consistently escaped before being used to build incremental-cache file paths, enabling path traversal on Windows filesystems.
  • Trigger conditions: the affected server must run on Windows, use the Pages Router and App Router without Cache Components enabled, use the default filesystem cache, and expose a dynamic ISR route (Pages Router), a dynamic cached route (App Router), and a closure-bound Server Action.
  • Attack vector: network, no authentication or user interaction required; the attacker crafts requests that manipulate the filesystem cache path and forges a Server Action invocation to reach a code-execution primitive, exfiltrating command output via an out-of-band callback.
  • Impact: disclosure of sensitive build artifacts (including encryption keys) and remote code execution on the host, with high impact to confidentiality, integrity, and availability.

Affected software

  • Next.js 13.4.0 through 15.5.23
  • Next.js 16.0.0 through 16.3.2
  • Only deployments running on Windows-hosted servers are exploitable for RCE

Severity

  • CVSS v3.1 Base Score: 9.0 (Critical)
  • Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

Mitigation and recommended actions

  • Immediate: upgrade to Next.js 15.5.24 or 16.3.3, which contain the fix.
  • If no patch can be applied immediately: there is no known workaround for affected Windows-hosted applications per the vendor advisory; prioritize migrating or isolating Windows-hosted Next.js deployments until patched, and restrict network access to these hosts where possible.

References

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report

How IONIX’s External Exposure Management Platform Detects and Validates
Zero-Days to Shrink MTTR

1

Map your entire attack surface (continously)

IONIX uses multi-factor discovery methods, including DNS analysis, certificate mapping, metadata inspection, and more, to automatically map every internet-facing asset across your environment. This includes cloud instances, third-party platforms, shadow IT, and even forgotten infrastructure that traditional tools miss.

2

Monitor for new CVEs

Dozens of threat intel feeds using agentic technology are continuously analyzed to detect the appearance of proof-of-concept code, exploit kits, and indicators of active targeting. IONIX goes further by applying AI to proactively evaluate whether emerging vulnerabilities are likely to be exploited, even before PoCs go public.

3

Identify Potential External Exposures

Not all CVEs matter. IONIX filters vulnerabilities by asking attacker-centric questions: Can it be reached from the internet? Does it require authentication? Is it being exploited in the wild? This dramatically reduces noise and focuses teams on threats that can actually be weaponized.

4

Create Safe, Scalable Exploit Validations

IONIX transforms real-world PoCs into safe, non-intrusive test payloads that can be run in production environments without disruption. These simulations are precisely targeted to the systems that are vulnerable, ensuring rapid validation without unnecessary load.

5

Execute Exploit Validations

By combining context about software stack, versioning, exposure status, and reachability, IONIX ensures that only the right payloads are executed against the right assets, maximizing efficiency and minimizing risk.

6

Drive Fast and Actionable Remediation

Results are routed through integrations with ticketing, SOAR, and SIEM tools. Issues are written in plain language, bundled into remediation clusters, and prioritized based on asset criticality, exploitability, and blast radius. This shortens mean time to remediation (MTTR) and empowers teams to act with confidence.

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report
Close

Subscribe to Threat Center RSS

Copy/paste the link below into your preferred RSS reader or follow these instructions to subscribe to Slack alerts.

Open RSS feedSlack setup instructions

Close

Get Real-Time CVE Alerts to Your Email

Be the first to know when new zero-days emerge