CVE-2025-52494Network attack vector

HTTPS service interruption via timeout-free TLS handshakes

Published Sep 3, 2025 · Updated Sep 3, 2025

Denial of service in AdaCore Ada Web Server before 26.0 allows remote attackers to block HTTPS service with a malformed ClientHello. During connection initialization, the server performs the SSL handshake before assigning a processing slot and leaves the socket timeout effectively infinite. Unauthenticated network access is sufficient; multiple incomplete handshakes can occupy every worker thread and prevent legitimate requests.

CVSS severity7.5
High
EPSS probability0.36%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in AdaCore Ada Web Server before 26.0 allows remote attackers to block HTTPS service with a malformed ClientHello. During connection initialization, the server performs the SSL handshake before assigning a processing slot and leaves the socket timeout effectively infinite. Unauthenticated network access is sufficient; multiple incomplete handshakes can occupy every worker thread and prevent legitimate requests.

The record

CVE
CVE-2025-52494
Published
Sep 3, 2025
Updated
Sep 3, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-770, CWE-400, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 3, 2025CVE publishedPublication date reported by the CVE source.
  2. Sep 3, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
7.5AdaCoreCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-770Allocation of Resources Without Limits or Throttling
CWE-400Uncontrolled Resource Consumption
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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