CVERadar
MEDIUM · CVSS 3.1 4.7Exploit-DBEPSS 0.52% (p43)Threat level 31

CVE-2026-14620: CVE-2026-14620: webpack-dev-server versions 5.2.5 and earlier expose two internal developer endpoints, /we…

webpack.js · webpack-dev-server · NVD published 2026-07-03 · posted 2026-08-17 · last modified 2026-07-07

What it is

webpack-dev-server versions 5.2.5 and earlier expose two internal developer endpoints, /webpack-dev-server/open-editor and /webpack-dev-server/invalidate, that perform state-changing actions on any GET request without verifying that the request originated from the dev server's own page. Any website a developer visits while the dev server is running can trigger these endpoints cross-origin with no interaction beyond the visit. An attacker can open an arbitrary existing local file in the developer's editor, including files outside the project root, and repeated requests can spawn editor processes and force recompilations that degrade the developer's machine. Patches: upgrade to webpack-dev-server 5.2.6. Workarounds: none.

WeaknessCWE-352CWE-749
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:L (source: [email protected])
ATT&CK tacticsExecution

Exploitation evidence

First exploit evidence seen: 2026-08-17 (earliest date across the sources below).

Exploited in the wild

No source on this site lists in-the-wild exploitation yet (CISA KEV, VulnCheck KEV).

Public exploit code

Exploit-DB

  • EDB-52649: webpack_devserver 5.2.5 - CSRF (2026-08-17)

Sources: Exploit-DB (OffSec).

Defend the Chain

The attack chain for CVE-2026-14620 laid across the MITRE ATT&CK Enterprise tactics. Solid cards come from the MITRE CTID KEV mappings; dashed cards are inferred by CVERadar from the CWE or description. Correct defences are real ATT&CK mitigations for that technique.

Threat level 31/100
Defender level 1 · 0 XP
Chain links broken: 0/1

Reconnaissance

Resource Development

Initial Access

Execution

Persistence

Privilege Escalation

Stealth

Defense Impairment

Credential Access

Discovery

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

Pick a red technique card on the board, then choose the defence that stops it.

Defend against T1204.001 Malicious Link Inferred

Inferred from CWE CWE-352

How to fix it

Fixed versions

  • webpack.js webpack-dev-server: upgrade to 5.2.6 or later

Derived from the NVD CPE configuration (versionEndExcluding / versionEndIncluding). Always confirm with the vendor advisory.

Vendor advisories and patches

MITRE ATT&CK mitigations for this chain

  • M1031 Network Intrusion Prevention (for T1204.001) : If a link is being visited by a user, network intrusion prevention systems and systems designed to scan and remove malicious downloads can be used to block activity.
  • M1017 User Training (for T1204.001) : Use user training as a way to bring awareness to common phishing and spearphishing techniques and how to raise suspicion for potentially malicious events.
  • M1021 Restrict Web-Based Content (for T1204.001) : If a link is being visited by a user, block unknown or unused files in transit by default that should not be downloaded or by policy from suspicious sites as a best practice to prevent some vectors, such as .scr, .exe, .pif, .cpl, etc. Some download scanning devices can open and analyze compressed and encrypted formats

Detection Generic guidance

  • Execution: Watch for the service process spawning shells or script interpreters (cmd.exe, powershell, sh, bash, python) via EDR process-tree rules.

Response checklist Generic guidance

  1. Inventory: find every instance of the affected product and version (include internet-facing and forgotten ones).
  2. Patch or mitigate per the vendor advisory; if you cannot patch, remove internet exposure or apply the vendor workaround.
  3. Assume compromise if the system was exposed before patching: hunt for the indicators in the advisory and review logs back to the disclosure date.
  4. Rotate credentials and secrets stored on or used by the affected system if compromise cannot be ruled out.

Sources