CVE-2026-56231
HIGH 7.2 PoC AVAILABLECapgo before 12.128.2 contains a broken object level authorization (BOLA) vulnerability in the POST /build/start/:jobId and POST /build/cancel/:jobId endpoints. The handlers authorize the request based only on the attacker-controlled app_id supplied in the request body and never verify that the jobId in the URL belongs to that app_id (or the same tenant/org) before issuing privileged builder commands with the server-held builder API key. An authenticated user with the app.build_native permission for any app they control can start or cancel arbitrary builder jobs belonging to other tenants by supplying a victim jobId, resulting in cross-tenant build sabotage (denial of service), unauthorized compute actions, and potential billing impact.
Public exploit or PoC code exists. Modeled probability is still low, but the barrier to attack is reduced — watch closely.
Exploitation likelihood
0.2%chance of exploitation in 30 days · 7th percentile
Impact if exploited
7.2CVSS 4.0 · HIGH
- ConfidentialityLow
- IntegrityLow
- AvailabilityHigh
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-72j4-9qp5-hfrg
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-56231/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-2026-56231/poc.json
Weakness (CWE)
- CWE-285: Improper Authorization
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N
All CVSS metrics
- HIGH 7.2 v4.0 · CNA Primary
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N - HIGH 7.6 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H - HIGH 7.2 v4.0 · NVD Secondary
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:H/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 7.6 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H