CVE-2026-56832: Praisonai PraisonAI DiscordApproval Accepts Unrelated Channel Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-8579-rgg5-ph2m",
  "modified" : "2026-07-20T21:23:11Z",
  "published" : "2026-06-18T13:52:27Z",
  "aliases" : [ "CVE-2026-56832" ],
  "summary" : "PraisonAI DiscordApproval accepts unrelated channel messages as dangerous-tool approvals",
  "details" : "# DiscordApproval accepts unrelated channel messages as dangerous-tool approvals\n\n## Summary\n\n`praisonai.bots.DiscordApproval` approves a pending dangerous tool call when it\nsees any later non-bot message in the configured Discord channel whose text is\nclassified as approval, such as `yes`.\n\nThe decision is not bound to:\n\n- a Discord reply to the approval message;\n- a Discord thread created for that request;\n- a Discord interaction/button callback for that request;\n- an explicit approver user allowlist; or\n- an approval nonce visible only to intended approvers.\n\nAs a result, any user who can post in the configured approval channel can\napprove a pending high-risk tool call by sending `yes` after the approval\nmessage appears. The same local PoV also shows that the Slack and Telegram\nmessaging approval backends have no explicit approver allowlist parameter, but\nthe primary report-grade issue is the Discord backend's unthreaded channel\ncross-talk: the approving message does not need to be a reply or otherwise\nrequest-bound.\n\n## Affected Product\n\n- Repository: `MervinPraison/PraisonAI`\n- Ecosystem: `pip`\n- Package: `praisonai`\n- Component: Python messaging approval backends\n- Primary affected file: `src/praisonai/praisonai/bots/_discord_approval.py`\n- Related sibling files:\n  - `src/praisonai/praisonai/bots/_slack_approval.py`\n  - `src/praisonai/praisonai/bots/_telegram_approval.py`\n- Latest PyPI version validated: `4.6.58`\n- Current `origin/main` validated:\n  `1ad58ca02975ff1398efeda694ea2ab78f20cf3e`\n- Current `origin/main` tag validated: `v4.6.58`\n\nSuggested affected range:\n\n```text\npip:praisonai >= 4.5.2, <= 4.6.58\n```\n\nRepresentative local sweep:\n\n```text\n4.5.0    Discord approval backend not present\n4.5.2    vulnerable\n4.5.128  vulnerable\n4.6.9    vulnerable\n4.6.10   vulnerable\n4.6.56   vulnerable\n4.6.57   vulnerable\n4.6.58   vulnerable\n```\n\n## Root Cause\n\n`DiscordApproval.request_approval()` posts an approval message to the configured\nchannel and records the returned message id.\n\n`_poll_for_response()` then polls channel history with:\n\n```python\nf\"/channels/{channel_id}/messages?after={message_id}&limit=10\"\n```\n\nFor each later non-bot message, it reads `content`, classifies the text, and\nreturns `ApprovalDecision(approved=True)` when the text is `approve`/`yes`.\nThere is no check that the message is a Discord reply to the approval message,\nbelongs to a request-specific thread, came from an intended approver, or\ncontains a request-specific approval token.\n\nImportant source evidence from `origin/main`:\n\n- `_discord_approval.py` lines 57-73: constructor accepts `token`,\n  `channel_id`, `timeout`, and `poll_interval`; no approver allowlist.\n- `_discord_approval.py` line 239: polls all messages after the approval\n  message in the configured channel.\n- `_discord_approval.py` lines 252-265: skips bot messages, classifies the\n  remaining text, and approves when the keyword is `approve`.\n\nThe Slack and Telegram backends are better request-scoped than Discord:\n\n- Slack uses `conversations.replies` for the approval message thread.\n- Telegram checks the callback/reply message id.\n\nHowever, both still lack an explicit approver identity parameter. They are\nincluded in the PoV and suggested fix because the authorization model should be\nconsistent across all messaging approval backends.\n\n## Local PoV\n\nRun against the latest local checkout:\n\n```bash\npython3 poc/pov_prai_cand_029_messaging_approval_channel_member_bypass.py \\\n  --repo ../../artifacts/repos/praisonai-v4.6.58 \\\n  --json\n```\n\nThe PoV is local-only. It mocks Slack, Telegram, and Discord API helpers\nin-process and does not contact those services.\n\nFor Discord, the mock sequence is:\n\n1. `DiscordApproval` posts a critical `execute_command` approval request to\n   `D_APPROVAL_CHANNEL`.\n2. The mocked channel-history endpoint returns a later ordinary non-bot\n   channel message from `D_INTRUDER` with content `yes`.\n3. `DiscordApproval` returns `approved=True` and `approver=\"D_INTRUDER\"`.\n\nObserved output from `evidence/pov-v4.6.58.json`:\n\n```json\n{\n  \"approval_from_unconfigured_channel_participant\": {\n    \"discord\": true,\n    \"slack\": true,\n    \"telegram\": true\n  },\n  \"backends\": [\n    {\n      \"backend\": \"discord\",\n      \"configured_channel_id\": \"D_APPROVAL_CHANNEL\",\n      \"decision_approved\": true,\n      \"decision_approver\": \"D_INTRUDER\",\n      \"decision_reason\": \"Approved via Discord by intruder\",\n      \"intruder_user\": \"D_INTRUDER\"\n    }\n  ],\n  \"no_explicit_approver_allowlist_parameters\": true,\n  \"vulnerable\": true\n}\n```\n\nThe command in the approval request is a harmless local sentinel:\n`touch /tmp/prai-cand-029`. The PoV stops at the approval decision; it does not\nexecute the tool.\n\n## Why This Is Not Intended Behavior\n\nThis report does not claim that a deliberately private approval channel with\nonly trusted approvers is unsafe by itself. The narrower issue is that the\nDiscord backend treats an unrelated later channel message as the approval\ndecision for a specific dangerous tool request.\n\nPraisonAI's approval documentation describes approval as a safety control that\npauses before dangerous tools and asks a human or channel to allow or deny the\nspecific request. A random later `yes` in the channel is not evidence that an\nintended approver reviewed that request.\n\nThe existing Slack and Telegram implementations already show request-binding\npatterns that Discord lacks:\n\n- Slack scopes to replies for the approval message timestamp.\n- Telegram checks the callback/reply `message_id`.\n\nThe Discord backend should provide at least the same request binding and should\nalso support explicit approver identity checks for deployments where channel\nmembership is broader than approval authority.\n\n## Impact\n\nIf an application uses `DiscordApproval` for dangerous tools such as shell\ncommands, file writes, deletes, deployments, or other privileged operations, a\nlow-privileged Discord user with write access to the configured approval channel\ncan approve pending dangerous tool executions.\n\nThis can lead to code execution, file modification, deployment changes, or data\naccess with the privileges of the PraisonAI process, depending on which tools\nthe agent exposes behind approval.\n\nThe attacker does not need the LLM API key, shell access, repository access, or\nPraisonAI process access. They only need to be able to post an approval-looking\nmessage in the configured approval channel after the approval prompt appears.\n\n## Severity\n\nSuggested severity: High.\n\nRationale:\n\n- `AV`: the attacker interacts through a networked Discord channel.\n- `AC`: sending `yes` after an approval prompt is enough.\n- `PR`: the attacker needs permission to post in the configured approval\n  channel, but no approver-specific permission.\n- `UI`: no separate victim interaction is needed after the prompt exists.\n- `S`: the vulnerable approval backend and approved tool run in the PraisonAI\n  application's security scope.\n- `C/I/A`: approved dangerous tools can disclose, modify, or destroy data\n  depending on the configured agent tools.\n\n## Remediation\n\nRecommended fixes:\n\n1. For Discord, require approvals to be tied to the request, not merely any\n   later channel message. Use Discord interactions/buttons with opaque\n   server-side request ids, or require a Discord reply whose\n   `message_reference.message_id` matches the approval message.\n2. Add explicit approver identity configuration to all messaging approval\n   backends, for example `approver_user_ids` or `allowed_approvers`.\n3. Reject approvals from users outside the configured approver set, even if the\n   message appears in the configured channel.\n4. Include a per-request nonce or opaque approval id in callbacks and verify it\n   server side before returning `ApprovalDecision(approved=True)`.\n5. Add regression tests for Discord where:\n   - an unrelated later `yes` in the channel is ignored;\n   - a reply from a non-approver is ignored;\n   - a request-bound reply/callback from an allowed approver succeeds.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "praisonai"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "4.5.2"
      }, {
        "fixed" : "4.6.59"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 4.6.58"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-8579-rgg5-ph2m"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/MervinPraison/PraisonAI"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-345", "CWE-863" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-06-18T13:52:27Z",
    "nvd_published_at" : null
  }
}