vulnerability / NVI-00008876 / Revision 1
NationalSecurityAgency/emissary has an incomplete fix for CVE-2026-35571
GitHub lists this reviewed advisory for gov.nsa.emissary:emissary. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
4.8 medium
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
gov.nsa.emissary:emissary
source listed< 8.51.0
### Summary The URL validation regex `^(https?:/)?/.*` added to emissary's `NavAction.java` allows protocol-relative URLs (`//evil.com/...`) and single-slash scheme variants (`http:/evil.com`) to bypass validation, enabling SSRF and open redirect attacks. ### Affected Package - **Ecosystem:** Maven - **Package:** NationalSecurityAgency/emissary - **Affected versions:** = e2078417464b ### Severity Medium ### CWE CWE-918 — Server-Side Request Forgery (SSRF) ### Details The fix in `NavAction.java` (line 47) introduces a `VALID_LINK` pattern: ```java Pattern.compile("^(https?:/)?/.*") ``` This regex is intended to restrict navigation links to relative paths and HTTP/HTTPS URLs. However, it has multiple bypass vectors. Protocol-relative URLs (`//evil.com/...`): The group `(https?:/)?` is optional, so the pattern reduces to `//.*` when the group is absent. This matches `//evil.com/steal?c=SESSION`, which browsers resolve to the current page's protocol plus the attacker's host. Single-slash scheme (`http:/evil.com`): The regex group captures `http:/` as a valid match, and browsers normalize `http:/evil.com` to `http://evil.com`, creatin
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-c6q7-wqw2-h65w ↗
GitHub Advisory Database · vendor advisory
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Public revision history
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- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.