Robert Luberda man2html 1.6g size heap-based overflow

CVSS Meta Temp Score
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CTI Interest Score
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5.4$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in Robert Luberda man2html 1.6g. The impacted element is an unknown function. The manipulation of the argument size leads to heap-based overflow. This vulnerability is traded as CVE-2021-40647. There is no exploit available.

Detailsinfo

A vulnerability was found in Robert Luberda man2html 1.6g. It has been rated as critical. This issue affects some unknown functionality. The manipulation of the argument size with an unknown input leads to a heap-based overflow vulnerability. Using CWE to declare the problem leads to CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). Impacted is confidentiality, integrity, and availability. The summary by CVE is:

In man2html 1.6g, a specific string being read in from a file will overwrite the size parameter in the top chunk of the heap. This at least causes the program to segmentation abort if the heap size parameter isn't aligned correctly. In version before GLIBC version 2.29 and aligned correctly, it allows arbitrary write anywhere in the programs memory.

The weakness was shared 09/10/2022. It is possible to read the advisory at gist.github.com. The identification of this vulnerability is CVE-2021-40647 since 09/07/2021. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 232331 (Fedora 41 : man2html (2025-538f2e492d)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Tenable (232331). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.4

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 232331
Nessus Name: Fedora 41 : man2html (2025-538f2e492d)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

09/07/2021 🔍
09/10/2022 +368 days 🔍
09/10/2022 +0 days 🔍
03/10/2025 +912 days 🔍

Sourcesinfo

Advisory: gist.github.com
Status: Not defined

CVE: CVE-2021-40647 (🔍)
GCVE (CVE): GCVE-0-2021-40647
GCVE (VulDB): GCVE-100-208259

Entryinfo

Created: 09/10/2022 08:36
Updated: 03/10/2025 20:33
Changes: 09/10/2022 08:36 (38), 10/15/2022 09:16 (10), 03/10/2025 20:33 (16)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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