CVE-2025-52494

HIGH
MEDIUM Priority: 0.03 BB Relevance: 75/100
Published: 2025-09-03 Modified: 2026-11-07 First seen: 2026-11-07 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
S: Unchanged
C: None
I: None
A: High

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.

Weakness Classification (2)

Affected Software (1)

VendorProductVersion
adacore ada_web_server < 26.0

References & Advisories (2)

Bug Bounty Relevance

75 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

7.5 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploitation Probability

0.36%
Raw Score 0.003550
Percentile 29.5%
Date 2026-11-10

EPSS Trend

2026-11-10
0.00355
2026-11-09
0.00355
2026-11-08
0.00355
2026-11-07
0.00355

Intelligence Sources

nvd ref →