All vulnerabilities
CVE-2026-42270GHSA-86cv-qwp9-jwp3

countly-server: Unauthenticated Denial of Service (DoS) via Unhandled Stream Exception

Countly countly-server
Open in ThreatlineRecord JSON
CVSS
7.5High
ExploitationPublic exploit codeCISA's assessment says proof of concept code is public, assessed 16 Oct 2026. Not in the KEV catalogCISA via CVE List
Exploit odds (EPSS)0.54%Chance of exploitation activity in the next 30 days, higher than 44% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed inNone listedNo source names a fixed version. Check the vendor advisory below
Published16 Oct 2026Updated 16 Oct 2026CVE List

What fixes it

No source in this snapshot names a fixed version. The vendor advisories under References are the place to check.

Description

countly-server is the server-side part of Countly, a product analytics solution. Prior to 24.05.50 and 25.03.44, star-rating/images/ and dashboards/images/screenshots/ are among public image and screenshot routes using the local fs storage backend that call getStream and pipe filesystem streams to HTTP responses without an error listener. An unauthenticated request containing a URL-encoded dot can make createReadStream open a directory, emit an asynchronous EISDIR error, and terminate the Node.js process as an unhandled exception, allowing repeated requests to keep the analytics API unavailable. The affected routes also include /appimages/*, /memberimages/*, and */screenshots/*. This issue is fixed in versions 24.05.50 and 25.03.44.

Text from CVE List

Affected versions 2

  • countly-serveraffected: < 24.05.50CVE List
  • countly-serveraffected: >= 25.03, < 25.03.44CVE List

References 5