libxml2 up to 2.9.10 XML Entity Encoding out-of-bounds

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability categorized as problematic has been discovered in libxml2 up to 2.9.10. Impacted is an unknown function of the component XML Entity Encoding Handler. Such manipulation leads to out-of-bounds. This vulnerability is referenced as CVE-2021-3517. It is possible to launch the attack remotely. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in libxml2 up to 2.9.10 (Document Processing Software). It has been rated as problematic. Affected by this issue is an unknown functionality of the component XML Entity Encoding Handler. The manipulation with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality.

The weakness was published 05/20/2021. The advisory is shared for download at bugzilla.redhat.com. This vulnerability is handled as CVE-2021-3517. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 236735 (Alibaba Cloud Linux 3 : 0047: libxml2 (ALINUX3-SA-2021:0047)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.9.11 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (236735). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.6
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 236735
Nessus Name: Alibaba Cloud Linux 3 : 0047: libxml2 (ALINUX3-SA-2021:0047)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: libxml2 2.9.11

Timelineinfo

04/27/2021 🔍
05/20/2021 +23 days 🔍
05/20/2021 +0 days 🔍
12/02/2025 +1657 days 🔍

Sourcesinfo

Advisory: bugzilla.redhat.com
Status: Confirmed

CVE: CVE-2021-3517 (🔍)
GCVE (CVE): GCVE-0-2021-3517
GCVE (VulDB): GCVE-100-175400

Entryinfo

Created: 05/20/2021 08:37
Updated: 12/02/2025 23:27
Changes: 05/20/2021 08:37 (38), 05/23/2021 07:22 (5), 05/16/2025 05:04 (16), 12/02/2025 23:27 (19)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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