SecurlyApplication

CVE-2026-8888

HIGH · 7.5 CVSS v3.1 Published 2026-06-03
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Version 3.0.7 of the Securly Chrome Extension downloads config.json over HTTP and compiles server-provided patterns as JavaScript regular expressions via new RegExp() without complexity validation. An on-path attacker can inject specific patterns to cause catastrophic backtracking, resulting in denial of service on all browsing.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

The Securly Chrome Extension v3.0.7 fetches its configuration file over unencrypted HTTP, allowing an on-path attacker to inject malicious content. The extension then compiles server-provided patterns directly as JavaScript regular expressions using new RegExp() without any complexity or backtracking validation, enabling attackers to inject crafted regex patterns that cause catastrophic backtracking and crash the browser tab.

MitigationEnforce HTTPS for all configuration downloads to prevent injection, and implement regex complexity validation (e.g., length limits, analysis of nested quantifiers) before compiling patterns with new RegExp(), or use a safe regex execution sandbox with timeouts.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
SecurlyApplication
Affected:= 3.0.7

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Verify Securly Chrome Extension version
    Open Chrome, navigate to chrome://extensions, enable Developer Mode in the top right, locate the Securly extension in the list, and read the version number displayed under the extension name
    Affected if The installed version is exactly 3.0.7
  2. Inspect network traffic for config download
    Open Chrome DevTools (F12), go to the Network tab, reload the browser or trigger the extension, filter for 'config.json' requests, and examine the protocol column to see if the request uses HTTP or HTTPS
    Affected if The extension makes a request to config.json using the HTTP protocol (http://) instead of HTTPS (https://)
  3. Examine extension source code for regex compilation
    In chrome://extensions, find the Securly extension, click 'Details', then click 'View in Chrome Web Store' or use 'Pack extension' to extract the CRX file, then inspect background.js or similar scripts for usage of new RegExp() with server-supplied data without complexity validation
    Affected if The extension code contains new RegExp() calls that accept remote configuration data without validating regex complexity or backtracking limits

You are affected if you have Securly Chrome Extension version 3.0.7 installed AND the extension downloads its configuration over unencrypted HTTP AND the extension compiles remote patterns as regex without validation.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Enforce HTTPS for all configuration downloads to prevent injection, and implement regex complexity validation (e.g., length limits, analysis of nested quantifiers) before compiling patterns with new RegExp(), or use a safe regex execution sandbox with timeouts.

Fix this in Securly Scoped from the published advisory
  • Consultation4.0 h
  • Implementation12.0 h
  • Testing6.0 h
  • Review / QA3.0 h
25.0 hours of engineering $4,400
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Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-8888 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
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