CVE-2025-34127 | BDVDB-2026-286390 Detail

Achat SoftwareAchat Chat Server

Description#

A stack-based buffer overflow exists in Achat v0.150 in its default configuration. By sending a specially crafted message to the UDP port 9256, an attacker can overwrite the structured exception handler (SEH) due to insufficient bounds checking on user-supplied input leading to remote code execution.

Impact#

CAPEC-100 Overflow Buffers

Weaknesses#

CWE-121 Stack-based Buffer Overflow
CWE-94 Improper Control of Generation of Code ('Code Injection')

References#

Exploit#

History#

Version 12025-07-16Record published in the CVE List.
Version 22026-04-07Most recent update recorded in the CVE List.

Published

Published: 2025-07-16
Last modified: 2026-04-07

Vendor information

Vendor: Achat Software
Product: Achat Chat Server

All Achat Software vulnerabilities

Score

9.3 Critical

EPSS

1.8%, Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 79.6.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Code Injection

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
0.150
Fixed
Not stated

Scoring System

CVSS v4.0

9.3 Critical

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Metric breakdown
Attack Vector	Network
Attack Complexity	Low
Attack Requirements	None
Privileges Required	None
User Interaction	None
Vulnerable System Confidentiality	High
Vulnerable System Integrity	High
Vulnerable System Availability	High
Subsequent System Confidentiality	None
Subsequent System Integrity	None
Subsequent System Availability	None

CVSS v3.1

Not available

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).