HylaFAX/HylaFAX+ Dial-In Session faxd/CopyQuality.c++ FaxModem::writeECMData input validation

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability classified as critical has been found in HylaFAX and HylaFAX+ (the affected version is unknown). Affected is the function FaxModem::writeECMData of the file faxd/CopyQuality.c++ of the component Dial-In Session Handler. The manipulation with an unknown input leads to a input validation vulnerability. CWE is classifying the issue as CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

HylaFAX 6.0.6 and HylaFAX+ 5.6.0 allow remote attackers to execute arbitrary code via a dial-in session that provides a FAX page with the JPEG bit enabled, which is mishandled in FaxModem::writeECMData() in the faxd/CopyQuality.c++ file.

The bug was discovered 09/20/2018. The weakness was published 09/21/2018 as not defined mailinglist post (Bugtraq). The advisory is shared for download at seclists.org. This vulnerability is traded as CVE-2018-17141 since 09/17/2018. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 1 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 117642 (Debian DLA-1515-1 : hylafax security update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Debian Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 176481 (Debian Security Update for hylafax (DSA 4298-1)).

Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.hylafax.org. A possible mitigation has been published 2 days after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (117642).



CPE 2.3info

CPE 2.2info


VulDB CVSS-B Score: 🔍
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VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.4

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
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NVD Base Score: 9.8
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Class: Input validation

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

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Nessus ID: 117642
Nessus Name: Debian DLA-1515-1 : hylafax security update
Nessus File: 🔍
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Threat Intelligenceinfo

Interest: 🔍
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Recommended: Patch
Status: 🔍

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Patch: c6cac8d8cd0dbe313689ba77023e12bc5b3027be


09/17/2018 🔍
09/20/2018 +3 days 🔍
09/21/2018 +0 days 🔍
09/21/2018 +0 days 🔍
09/22/2018 +1 days 🔍
09/22/2018 +0 days 🔍
09/24/2018 +2 days 🔍
05/17/2023 +1696 days 🔍


Advisory: DLA 1515-1
Status: Not defined
Confirmation: 🔍

CVE: CVE-2018-17141 (🔍)


Created: 09/22/2018 07:33 AM
Updated: 05/17/2023 03:14 PM
Changes: 09/22/2018 07:33 AM (75), 03/26/2020 03:26 PM (2), 05/17/2023 03:14 PM (5)
Complete: 🔍
Cache ID: 100:D59:40


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