CVE-2025-52494
Adacore Ada Web Server (AWS) before 25.2 is vulnerable to a denial-of-service (DoS) condition due to improper handling of SSL handshakes during connection initialization.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.36%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Adacore Ada Web Server (AWS) before 25.2 is vulnerable to a denial-of-service (DoS) condition due to improper handling of SSL handshakes during connection initialization. When a client initiates an HTTPS connection, the server performs the SSL handshake before assigning the connection to a processing slot. However, there is no specific timeout set for this phase, and the server uses the default socket timeout, which is effectively infinite. An attacker can exploit this by sending a malformed TLS ClientHello message with incorrect length values. This causes the server to wait indefinitely for data that never arrives, blocking the worker thread (Line) handling the connection. By opening multiple such connections, up to the server's maximum limit, the attacker can exhaust all available working threads, preventing the server from handling new, legitimate requests.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.36% probability · 29th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-400, CWE-770
- Affected
- adacore/ada web server
- Source
- cve@mitre.org
References
- https://adacore.comProduct
- https://docs.adacore.com/corp/security-advisories/SEC.AWS-0095-v1.pdfTechnical Description, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.