CVE-2025-27777
Published: 19 March 2025
Summary
CVE-2025-27777 is a high-severity SSRF (CWE-918) vulnerability in Applio Applio. Its CVSS base score is 7.7 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 49.6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 AC-4 (Information Flow Enforcement) and SC-7 (Boundary Protection).
Deeper analysis
CVE-2025-27777 is a server-side request forgery (SSRF) vulnerability in Applio, an open-source voice conversion tool. Versions 3.2.7 and prior are affected, with the flaw located in the `model_download.py` file at line 195. This blind SSRF allows attackers to force the Applio server to send requests on their behalf, as documented in the CVE description and referenced GitHub code locations including `assets/flask/routes.py` and `tabs/download/download.py`. The vulnerability is rated 7.5 (High) under CVSS 3.1 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N) and maps to CWE-918.
Any unauthenticated attacker with network access to the Applio server can exploit this blind SSRF to probe for other vulnerabilities on the server itself or on backend systems reachable by the Applio server within the internal network. Exploitation enables port scanning, service discovery, or chaining with other issues, such as the arbitrary file read in CVE-2025-27784, to achieve full SSRF and read files from internal hosts accessible to the server.
The GitHub Security Lab advisory (GHSL-2024-341_GHSL-2024-353_Applio) details the issue but notes that, as of publication on 2025-03-19, no patches are available for this vulnerability. Security practitioners should monitor the Applio repository for updates and consider network segmentation or disabling the affected model download functionality until remediation is released.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-6789
Vulnerability details
Applio is a voice conversion tool. Versions 3.2.7 and prior are vulnerable to server-side request forgery (SSRF) in `model_download.py` (line 195 in 3.2.7). The blind SSRF allows for sending requests on behalf of Applio server and can be leveraged to…
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probe for other vulnerabilities on the server itself or on other back-end systems on the internal network, that the Applio server can reach. The blind SSRF can also be coupled with a arbitrary file read (e.g., CVE-2025-27784) to read files from hosts on the internal network, that the Applio server can reach, which would make it a full SSRF. As of time of publication, no known patches are available.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
SSRF in public-facing web app directly enables exploitation via T1190; blind SSRF facilitates internal port scanning and service discovery via T1046.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Requires validation of user-supplied inputs like URLs in model_download.py to block malicious SSRF requests to internal systems.
Implements boundary protections such as firewalls to restrict Applio server's outbound access to internal network resources exploitable via blind SSRF.
Enforces information flow policies to prevent unauthorized requests from the Applio server to backend systems during SSRF exploitation.