CVE-2026-56243
HIGH 8.6 PoC AVAILABLECapgo before 12.128.2 contains a security control bypass vulnerability where the PostgREST/RLS plane accepts plaintext API keys through the capgkey header despite enforce_hashed_api_keys being enabled. Attackers can bypass org-level hashed-key enforcement by sending plaintext API keys directly to the PostgREST/RLS plane to access protected resources.
Public exploit or PoC code exists. Modeled probability is still low, but the barrier to attack is reduced — watch closely.
Exploitation likelihood
0.3%chance of exploitation in 30 days · 19th percentile
Impact if exploited
8.6CVSS 4.0 · HIGH
- ConfidentialityHigh
- IntegrityHigh
- AvailabilityNone
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ⚠Privileges: Requires a low-privilege account
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
- ✓Requirements: No special attack requirements
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- reference https://github.com/Cap-go/capgo/security/advisories/GHSA-6g74-8cpq-g2c8
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-56243/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-56243/poc.json
Weakness (CWE)
- CWE-288: Authentication Bypass Using an Alternate Path or Channel
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
All CVSS metrics
- HIGH 8.6 v4.0 · CNA Primary
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N - HIGH 8.1 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N - HIGH 8.6 v4.0 · NVD Secondary
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - HIGH 8.1 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N