Plesk Obsidian: cross-subscription disclosure in GoAccess statistics (CVE-2026-82977)

An affected Plesk Obsidian GoAccess deployment can expose web statistics across subscriptions. Apply the Plesk fix to keep one subscription’s statistics private from another.

Public CVE record · Vendor or publisher advisory · Native module source

CVE advisory record · Vendor advisory · Module source

Result. The marked request reached the backend in the baseline and raised its counter. The native rule refused that request with HTTP 403 and preserved HTTP 200 for the benign probe. The synthetic fixture ran through Eden 1.103.0 on November 12, 2026 (UTC).

The vulnerability

Plesk’s GoAccess integration generates web statistics for hosted subscriptions. The security boundary is between subscriptions on the same host. The advisory identifies cross-subscription information disclosure in affected Plesk Obsidian for Linux releases.

The advisory lists 18.0.77–18.0.81.7 and 18.0.82–18.0.82.2 as affected. Consult the Plesk advisory for release-specific remediation. The CVE record reports a CVSS base score of 8.4.

The Eden patch

Tier 1 — declarative policy. The recorded policy denies requests to /goaccess and its descendants. The empty method list leaves the deny unrestricted by HTTP method. This is a coarse rule and blocked the benign probe on the same path.

{
  "version": 1,
  "profile": "http-structure-v1",
  "policy": {
    "version": 1,
    "rules": [
      {
        "scope": {
          "methods": [],
          "path": "/goaccess",
          "descendants": true
        },
        "require": {
          "kind": "deny"
        }
      }
    ]
  }
}

Tier 2 — native Rust module. gabriel_pleskstat_v1 waits for the request to be complete, checks whether the request target starts with /goaccess, and looks for any configured marker in the body. The substring comparison is ASCII case-insensitive. Outside that prefix or without a marker, the module returns Continue. The shown lines are excerpts from the linked source.

const ROUTE: &[u8] = b"/goaccess";
static NEEDLES: [&[u8]; 2] = [b"/var/log/", b"../"];

NEEDLES.iter().any(|n| find_ignore_case(body, n).is_some()) && return Ok(Decision::Refuse);

Implement the remediation

Use this procedure in an isolated fixture to reproduce the scoped restriction. Follow the vendor update for the underlying exposure. See deployment prerequisites.

1. Prepare the target. Verify the loaded product and version against the advisory. Use a compatible Eden HTTP interlay and an authenticated operator with Configure permission. Use the recorded declaration and the linked source when applicable.
2. Apply the declarative policy. Scope the policy to /goaccess and descendants (all methods, deny). Set INTERLAY to the target interlay UUID in the authenticated Eden CLI. Run an authenticated GET /api/v1/interlays/{interlay} with X-Eden-Verbose: true. Save its complete current settings object as current-settings.json and retain the prior remediation declaration for recovery. Set IDEMPOTENCY_KEY to a fresh key for this intended mutation.

Save the JSON in the patch section as remediation.json.

jq -e --slurpfile policy remediation.json \
  '.remediation = $policy[0] | {settings: .}' current-settings.json \
  > interlay-update.json
eden api request PATCH "/api/v1/interlays/$INTERLAY" \
  --header "Idempotency-Key:$IDEMPOTENCY_KEY" \
  --body-file interlay-update.json --content-type application/json --confirm

3. Verify the serving policy. Read back the interlay.

eden api request GET "/api/v1/interlays/$INTERLAY" \
  --header 'X-Eden-Verbose:true'

Check that remediation_status.state is ready and both desired and effective SHA-256 values match the intended declaration. Replay the benign and marked requests in the recorded comparison on an isolated target. Check the recorded response and backend outcome for each probe. 4. Restore the previous policy. Coordinate the change with any other operator updating this interlay. Read current settings again and merge the saved remediation field into them. If the prior settings had no remediation field, omit it in the replacement. Send the same PATCH with a fresh idempotency key, then read back the intended state. Repeat the verification probes. Keep the affected route isolated if restoring the prior settings reopens exposure.

Vendor update. Use the advisory to identify the supported update or workaround for the installed release. The advisory data used here supplies no fixed version. Confirm the running version and verify the affected feature after the change.

Fixture and probes

The fixture was a synthetic HTTP handler behind Eden. It answered the probes and kept a separate counter that increased when the handler recognized its marker bytes. The counter measures a fixture effect. An HTTP 200 from the baseline does not by itself establish that the counter moved.

Request. POST /goaccess/stats for the benign probe and the marked probe.

The benign fixture body requested a weekly report. The second supplied a log-path string and parent directory fragments. The synthetic handler recorded those bytes without reading any log or checking account permissions.

Measured comparison (2026-11-12 UTC)

The values after each status are the observed increases in the backend marker counter.

Request latency

Eden telemetry request spans measured in the fixture. Latencies are in microseconds (µs).

These are durations of the recorded request spans. The passing request includes the path to the fixture, while the policy and native refusal rows describe requests that ended at Eden. The rows represent different request outcomes, so their difference does not isolate module CPU time. The sample counts are shown for each arm.

Signed module authority

The module import returned HTTP 201 and required explicit activation. Signature verification was deferred at import. Read-only inspection returned HTTP 403, admission with a tampered statement returned HTTP 400, and admission with an invalid signature returned HTTP 403. The activation receipt reported the module serving on all expected shards.

After revocation, the same marked request received HTTP 503. Re-approval and reactivation restored HTTP 403. The source digest below identifies the linked Rust file. The binary digest identifies the artifact recorded in the activation evidence.

• Source SHA-256 f2a0d634f945ecee9408c8cc7a38780519fb768ea7c225a1314651a1bf0c7ceb
• Tested binary SHA-256 4f00805a874f085cd6fcf7784975713cf5c65517417408615968d6124d57563d

Test scope

The module scans request bodies for path fragments. The advisory’s cross-subscription authorization failure remains unverified. A correct-looking request to a different subscription is not something this byte matcher can distinguish. Legitimate report configuration containing a log path can also match.

Evidence and artifacts

• Public CVE record
• Vendor or publisher advisory
• Published module source