Phoenix.HTML up to 3.0.3 Class Attribute tag.ex cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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4.7$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in Phoenix.HTML up to 3.0.3. The affected element is an unknown function of the file tag.ex of the component Class Attribute Handler. Such manipulation leads to cross site scripting. This vulnerability is traded as CVE-2021-46871. The attack may be launched remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Phoenix.HTML up to 3.0.3. Affected by this issue is an unknown function of the file tag.ex of the component Class Attribute Handler. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. CVE summarizes:

tag.ex in Phoenix Phoenix.HTML (aka phoenix_html) before 3.0.4 allows XSS in HEEx class attributes.

The weakness was shared 01/10/2023 as GHSA-j3gg-r6gp-95q2. The advisory is shared for download at github.com. This vulnerability is handled as CVE-2021-46871 since 01/10/2023. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1059.007.

Upgrading to version 3.0.4 eliminates this vulnerability. Applying the patch 62a0139fb716bcdce697f6221244bd81d321d620 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 3.5
VulDB Temp Score: 3.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.1
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Phoenix.HTML 3.0.4
Patch: 62a0139fb716bcdce697f6221244bd81d321d620

Timelineinfo

01/10/2023 🔍
01/10/2023 +0 days 🔍
01/10/2023 +0 days 🔍
04/09/2025 +820 days 🔍

Sourcesinfo

Advisory: GHSA-j3gg-r6gp-95q2
Status: Confirmed

CVE: CVE-2021-46871 (🔍)
GCVE (CVE): GCVE-0-2021-46871
GCVE (VulDB): GCVE-100-217784

Entryinfo

Created: 01/10/2023 14:55
Updated: 04/09/2025 20:27
Changes: 01/10/2023 14:55 (43), 01/31/2023 08:35 (11), 04/09/2025 20:27 (16)
Complete: 🔍
Cache ID: 216::103

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