Flow-Like: Azure invoke presign grants app content write SAS to ExecuteEvents-only users

published 2026-08-19 2 mo ago modified 2026-09-18 51 d ago also EUVD-2026-62589

cvss: 7.2; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 52%
public exploits: 0; none known

Flow-Like is a platform for building end-to-end use cases. Prior to version 1.0.4, `GET /api/v1/apps/{app_id}/invoke/presign` grants Azure Blob Storage SAS credentials with write and delete access to app content to any app member that has `ExecuteEvents`, even when that member lacks `ReadFiles` and `WriteFiles`. The route treats file permissions as optional after the `ExecuteEvents` gate. When the caller has neither file permission, it selects `CredentialsAccess::InvokeNone`. In the Azure credential provider, `InvokeNone` still mints a `content_sas_token` for `apps/{app_id}` with `sp=rwdl`, plus user-content and log SAS tokens. The returned shared credential is enough for the low-privilege caller to directly write or delete blobs under the app content prefix. Version 1.0.4 patches the issue. Flow-Like Studio and the hosted Flow-Like Web App are not affected. These deployments use AWS-backed storage. Self-hosted deployments are only affected if they use Azure Blob Storage as the storage backend. In affected deployments, the issue only applies to authenticated app members who have workflow execution permissions but should not have app file write/delete permissions. Users of affected self-hosted Azure deployments should update to version 1.0.4 or the latest dev branch.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: partial
Assessed: 2 mo ago (2026-08-19)

Exploit prediction

0.68% chance of exploitation in the next 30 days, higher than 52% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/Rheosoph/flow-like/security/advisories/GHSA-99w9-5gvv-4v78 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	7.2	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N
CNA	4.0	7.2	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:H/VA:L/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

Affected products

Rheosoph flow-like

Classification

Weakness

CWE-863 Incorrect Authorization

References

github.com /Rheosoph/flow-like/security/advisories/GHSA-99w9-5gvv-4v78
exploit

Sources

CVE List CVE-2026-50173
NVD CVE-2026-50173

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary