Possible SSRF via WebSphere Portal docpicker internal_proxy CVE-2021-27748

PremiumReviewedSigma · Medium · v1
Category
webserver
Author
HuntRule
Published
2026-09-07
Updated
2026-09-07

ATT&CK techniques

Initial Access
  1. Recon

  2. Resource Dev

  3. Execution

  4. Persistence

  5. Priv Esc

  6. Defense Evasion

  7. Cred Access

  8. Discovery

  9. Lateral Movement

  10. Collection

  11. C2

  12. Exfiltration

  13. Impact

What it detects

This rule detects HTTP requests to the WebSphere Portal docpicker internal_proxy and wps proxy passthrough endpoints. CVE-2021-27748 exposes these proxy paths to server-side request forgery as described by Assetnote, which attackers use to reach internal-only services from the portal server.

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Possible SSRF via WebSphere Portal docpicker internal_proxy CVE-2021-27748
Pivot detection · T1190 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.