CVE-2026-58200: Signature Bypass (CVSS 7.1)

Description

Payload Plugins is a collection of plugins designed to enhance Payload CMS. From 0.3.0 until 0.4.0, @jhb.software/payload-cloudinary-plugin deployments with clientUploads enabled expose POST /api/cloudinary-generate-signature, whose handler in cloudinary/src/getGenerateSignature.ts passes attacker-controlled body.paramsToSign directly to cloudinary.utils.api_sign_request without a key allowlist, collection policy, timestamp freshness check, or configured-folder enforcement. Any authenticated Payload user can obtain a valid Cloudinary HMAC-SHA1 signature for unauthorized parameters such as overwrite, type, notification_url, invalidate, folder, and public_id. The signature can authorize asset replacement, upload visibility changes, callbacks to attacker-selected URLs, cache invalidation, and uploads outside the intended folder. The client-visible Cloudinary API key is expected by the upload design, but the unrestricted server-side signature supplies the authorization value needed to complete these operations. This vulnerability is fixed in 0.4.0.

Is your site exposed to CVE-2026-58200?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

7.1

HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L

EPSS — Exploit Prediction

0.0019

Probability of exploitation

0.08%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-347 CWE-347

References

Other References

https://github.com/jhb-software/payload-plugins/commit/da2325901c5eeced17d33a1b2e647e300b8cbff2 https://github.com/jhb-software/payload-plugins/pull/155 https://github.com/jhb-software/payload-plugins/releases/tag/[email protected] https://github.com/jhb-software/payload-plugins/security/advisories/GHSA-h5x8-xp6m-x6q4

Frequently Asked Questions

What is CVE-2026-58200? +

Payload Plugins is a collection of plugins designed to enhance Payload CMS. From 0.3.0 until 0.4.0, @jhb.software/payload-cloudinary-plugin deployments with clientUploads enabled expose POST /api/cloudinary-generate-signature, whose handler in cloudinary/src/getGenerateSignature.ts passes attacker-controlled body.paramsToSign directly to cloudinary.utils.api_sign_request without a key allowlist, collection policy, timestamp freshness check, or configured-folder enforcement. Any authenticated Payload user can obtain a valid Cloudinary HMAC-SHA1 signature for unauthorized parameters such as overwrite, type, notification_url, invalidate, folder, and public_id. The signature can authorize asset replacement, upload visibility changes, callbacks to attacker-selected URLs, cache invalidation, and uploads outside the intended folder. The client-visible Cloudinary API key is expected by the upload design, but the unrestricted server-side signature supplies the authorization value needed to complete these operations. This vulnerability is fixed in 0.4.0. It has a CVSS v3.1 base score of 7.1 (HIGH).

How severe is CVE-2026-58200? +

CVE-2026-58200 has a CVSS v3.1 score of 7.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0019, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-58200? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-46684

DataEase is an open source data visualization and analysis tool. Prior to 2.10.23, DataEase enterprise token handling can let TokenFilter#doFilter() …

CVE-2026-67278

MikroTik RouterOS accepts malformed RSA/PKCS#1 v1.5 signatures during X.509 validation. Because its trust store includes an e=3 root CA, an …

CVE-2026-59639

In Bouncy Castle for Java before 1.85, CMS verifySignatures returns true for SignedData with zero signers. This issue also affects …

CVE-2026-12860

In Bouncy Castle for Java before 1.85, RSA PKCS#1 verification skips last two hash bytes in NULL-omitted path. This issue …

CVE-2026-44720

OpenLearnX is an open-source, decentralized learning and assessment platform. Prior to 2.0.4, a critical authentication vulnerability was identified in OpenLearnX …

CVE-2025-24800

Hyperbridge is a hyper-scalable coprocessor for verifiable, cross-chain interoperability. A critical vulnerability was discovered in the ismp-grandpa crate, that allowed …

CVE-2026-58200