Xlight FTP Server up to 3.9.4 GCM Decrypt GCM decrypt function stack-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
9.5$0-$5k1.75

Summaryinfo

A vulnerability described as very critical has been identified in Xlight FTP Server up to 3.9.4. This vulnerability affects the function GCM decrypt function of the component GCM Decrypt. Such manipulation leads to stack-based overflow. This vulnerability is referenced as CVE-2026-67192. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability was found in Xlight FTP Server up to 3.9.4. It has been rated as very critical. Affected by this issue is the function GCM decrypt function of the component GCM Decrypt. The manipulation with an unknown input leads to a stack-based overflow vulnerability. Using CWE to declare the problem leads to CWE-121. A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). Impacted is confidentiality, integrity, and availability. CVE summarizes:

Xlight FTP Server before 3.9.5 contains a pre-authentication stack buffer overflow vulnerability that allows unauthenticated attackers to corrupt stack memory by sending malformed SSH packets when a GCM cipher is negotiated. Attackers can craft packets with an unvalidated length field passed directly to the GCM decrypt function, overwriting the stack cookie and return address to potentially achieve remote code execution before any authentication occurs.

The advisory is shared for download at xlightftpd.com. This vulnerability is handled as CVE-2026-67192 since 07/28/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 07/29/2026).

Upgrading to version 3.9.5 eliminates this vulnerability.

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Productinfo

Type

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 10.0
VulDB Meta Temp Score: 9.5

VulDB Base Score: 10.0
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Stack-based overflow
CWE: CWE-121 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: FTP Server 3.9.5

Timelineinfo

07/28/2026 CVE reserved
07/29/2026 +1 days Advisory disclosed
07/29/2026 +0 days VulDB entry created
07/29/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: xlightftpd.com
Status: Confirmed

CVE: CVE-2026-67192 (🔒)
GCVE (CVE): GCVE-0-2026-67192
GCVE (VulDB): GCVE-100-384200

Entryinfo

Created: 07/29/2026 18:28
Changes: 07/29/2026 18:28 (56)
Complete: 🔍
Cache ID: 216::103

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