Glean: Server-Side Request Forgery (SSRF) with Full Response Disclosure via Malicious RSS Feed in /api/feeds/discover
cve-program · CVE-2026-54339 · Published
No access to your tenant or devices. Every item links to its source. What this means
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.
Read the publisher's advisoryCISA KEV lists vulnerabilities known to be exploited. FIRST EPSS estimates the likelihood of exploitation in the next 30 days. An unavailable score does not mean zero risk.
This view includes predictions for CVE identifiers explicitly listed in public NuGet advisories. Microsoft release pages have their own prediction coverage. Check source status for the scope and latest checks.
No exploitation or prediction data is available here for these CVEs. This does not mean they are safe or unlikely to be exploited.
Compare earlier KEV listings and daily EPSS scores. Advisory wording and affected versions have a separate history.
A prediction change is reported when EPSS rises from below 10% to 10% or higher. Other daily score changes remain in this history.
See how the publisher's advisory changed over time. Each link opens the version saved at that time. The publisher's update date can differ from the date shown here.
Each link identifies one complete publisher record. History can include advisories that previously shared an identifier; an identifier removed by a publisher no longer establishes a current relationship. A historical link shows only that record and earlier saved versions. Failed checks and unchanged reads do not create new versions.
cve-program · CVE-2026-54339 · Published