CVE-2026-77759IDOR and missing authorization in the Prospero Flow CRM transaction API allow cross-tenant reading of financial records
- 8.7HighCVSS base score
- 0.51%Exploitation in 30 daysEPSS · top 56% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Authorization Bypass Through User-Controlled Key in the transaction API in Roskus Prospero Flow CRM 5.0.0 through 5.3.5 allows an authenticated user to read the transactions of other companies on the same instance via an incremented identifier in GET /api/transaction/{id}, which is resolved without company scoping and without any permission check.
Timeline
ID reserved
By Secur0
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| Secur0CNA (assigner) | 4.0 | High8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N |
| NVDNVD · Deferred | 4.0 | High8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/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 |
- EPSS (exploitation in 30 days)
- 0.51% · top 56% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.7.
Affected products
- affected 5.0.0 – < 5.3.6
What to do
Solution: Upgrade to 5.3.6 or later. The fix was not tagged; the first tagged release carrying it is v5.5.3.
References
References3
- https://github.com/Roskus/prospero-flow-crm/commit/980c35ac00e419591a8adc2d1dbcc120ea62e273 (opens in a new tab)patch
- https://github.com/Roskus/prospero-flow-crm/releases/tag/v5.5.3 (opens in a new tab)release-notes
- https://secur0.com/en/cna/cve-list/cve-2026-77759-idor-missing-authz-prospero-transaction-api (opens in a new tab)technical-descriptionthird-party-advisory
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-63906 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-77759)Record last updated .