CVE-2026-56339 (CVSS 7.5)

Description

Capgo (Cap-go/capgo) before 12.128.2 contains an information disclosure vulnerability in the Supabase PostgREST SECURITY DEFINER RPC function public.rescind_invitation that allows unauthenticated attackers to enumerate organization existence. The function returns distinct error messages (NO_ORG vs NO_RIGHTS) when called with only a publishable API key, enabling attackers to discover valid organization IDs and increase the attack surface for targeted phishing or social engineering campaigns.

Is your site exposed to CVE-2026-56339?

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

CVSS v3.1 Score

7.5

HIGH

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

EPSS — Exploit Prediction

0.0028

Probability of exploitation

0.20%

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-203 CWE-203

References

Other References

https://github.com/Cap-go/capgo/security/advisories/GHSA-8432-3cgm-vw5j https://www.vulncheck.com/advisories/capgo-unauthenticated-organization-existence-enumeration-via-rescind-invitation-rpc https://github.com/Cap-go/capgo/security/advisories/GHSA-8432-3cgm-vw5j

Frequently Asked Questions

What is CVE-2026-56339? +

Capgo (Cap-go/capgo) before 12.128.2 contains an information disclosure vulnerability in the Supabase PostgREST SECURITY DEFINER RPC function public.rescind_invitation that allows unauthenticated attackers to enumerate organization existence. The function returns distinct error messages (NO_ORG vs NO_RIGHTS) when called with only a publishable API key, enabling attackers to discover valid organization IDs and increase the attack surface for targeted phishing or social engineering campaigns. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-56339? +

CVE-2026-56339 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0028, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-56339? +

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-2026-65626

The pure-Erlang RSAES-PKCS1-v1_5 decryption in the jose_jwa_pkcs1 module is a Bleichenbacher padding oracle. eme_pkcs1_decode/2 returns the recovered message when a …

CVE-2025-24506

A specific authentication strategy allows to learn ids of PAM users associated with certain authentication types.

CVE-2026-84461

Zammad is a web based open source helpdesk/customer support system. Prior to 7.1.2, the two-factor login step let an attacker …

CVE-2026-55555

Dompdf is an HTML to PDF converter for PHP. Versions 3.15 and prior are vulnerable to a File Existence Oracle …

CVE-2026-114199

`GET /api/v1/users/{username}/heatmap` computed the contribution heatmap with the repository access of the token owner and ignored the public-only restriction of …

CVE-2026-63567

Observable discrepancy in IesEngine.DecryptBlock in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote attacker who has …