Internal response disclosure via unvalidated RSS item URLs
Published Sep 17, 2026 · Updated Sep 17, 2026
SSRF in Glean before 0.2.6 allows remote authenticated users to read internal HTTP responses through a malicious RSS feed. Feed discovery accepts feed_url, and the worker later sends each parsed item URL to fetch_and_extract_fulltext without network-level validation. An account able to add a feed can make the server reach private, loopback, link-local, or metadata endpoints and retrieve stored responses.
Summary
What happened
SSRF in Glean before 0.2.6 allows remote authenticated users to read internal HTTP responses through a malicious RSS feed. Feed discovery accepts feed_url, and the worker later sends each parsed item URL to fetch_and_extract_fulltext without network-level validation. An account able to add a feed can make the server reach private, loopback, link-local, or metadata endpoints and retrieve stored responses.
The record
- CVE
- CVE-2026-54339
- Published
- Sep 17, 2026
- Updated
- Sep 17, 2026
- Vendor
- Leslie Leung
- Product
- Glean
- Classifications
- CWE-918, T1190
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 17, 2026CVE publishedPublication date reported by the CVE source.
- Sep 17, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=< 0.2.6
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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