CVE-2026-5321 json
vanna-ai vanna FastAPI/Flask Server cross-domain policy
published 7mo ago modified 4mo ago also EUVD-2026-18122
- cvss
- 4.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 5%
- public exploits
- 0
- none known
Summary
A flaw has been found in vanna-ai vanna up to 2.0.2. Affected by this issue is some unknown functionality of the component FastAPI/Flask Server. Executing a manipulation can lead to permissive cross-domain policy with untrusted domains. The attack can be launched remotely. The exploit has been published and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 7mo ago
Exploit prediction
0.17% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-11).
Exploits and checks
- github.com https://github.com/August829/CVEP/issues/14 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P |
| CNA | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R |
| CNA | 3.0 | 4.3 | CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N/E:P/RL:X/RC:R |
| CNA | 2.0 | 4.0 | AV:N/AC:L/Au:S/C:N/I:P/A:N/E:POC/RL:ND/RC:UR |
| CNA | 4.0 | 2.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/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 |
| CNA | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N |
| CNA | 2.0 | 4.0 | AV:N/AC:L/Au:S/C:N/I:P/A:N |
Affected products
- vanna-ai vanna
Classification
References
-
github.com
/August829/CVEP/issues/14
exploit, issue-tracking
-
vuldb.com
/vuln/354653
vdb-entry
-
vuldb.com
/vuln/354653/cti
signature, permissions-required
-
vuldb.com
/submit/780729
third-party-advisory
Sources
- CVE List CVE-2026-5321
- NVD CVE-2026-5321
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