LeslieLeung Glean up to 0.2.5 Feed Fetcher extractor.py fetch_and_extract_fulltext feed_url server-side request forgery

Summaryinfo

A vulnerability was found in LeslieLeung Glean up to 0.2.5. It has been declared as problematic. This issue affects the function fetch_and_extract_fulltext of the file backend/packages/rss/glean_rss/extractor.py of the component Feed Fetcher. The manipulation of the argument feed_url results in server-side request forgery. This vulnerability is known as CVE-2026-54339. It is possible to launch the attack remotely. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in LeslieLeung Glean up to 0.2.5. Affected is the function fetch_and_extract_fulltext of the file backend/packages/rss/glean_rss/extractor.py of the component Feed Fetcher. The manipulation of the argument feed_url with an unknown input leads to a server-side request forgery vulnerability. CWE is classifying the issue as CWE-918. The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. This is going to have an impact on confidentiality. CVE summarizes:

Glean is a self-hosted RSS reader and personal knowledge management tool. Prior to 0.2.6, POST /api/feeds/discover passes an attacker-supplied feed_url to discover_feed(feed_url), creates a subscription through FeedService.create_subscription(), and enqueues fetch_feed_task. The background path calls fetch_feed(feed.url) and parse_feed(), which assigns each RSS item link to ParsedEntry.url. The task then passes ParsedEntry.url to fetch_and_extract_fulltext(parsed_entry.url) without network-level validation in backend/packages/rss/glean_rss/extractor.py and backend/apps/worker/glean_worker/tasks/feed_fetcher.py. A malicious feed can therefore make the server request private, loopback, link-local, or cloud-metadata resources. The fetched response is stored in Entry.content and can be retrieved through GET /api/entries/{id}, producing non-blind server-side request forgery with full response disclosure. This can bypass network perimeters, probe internal services and ports, expose internal configuration or web content, and potentially disclose cloud metadata access tokens. This issue is fixed in version 0.2.6.

The advisory is available at github.com. This vulnerability is traded as CVE-2026-54339 since 06/12/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Technical details are known, but there is no available exploit.

Upgrading to version 0.2.6 eliminates this vulnerability.

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Productinfo

Vendor

• LeslieLeung

Name

• Glean

Version

• 0.2.0
• 0.2.1
• 0.2.2
• 0.2.3
• 0.2.4
• 0.2.5

Website

• Product: https://github.com/LeslieLeung/glean/

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