CVE-2026-40451: Cross-site scripting (XSS) in DeepL Chrome browser extension
A cross-site scripting (XSS) vulnerability exists in the DeepL Chrome browser extension versions 1. 22. 0 through 1. 23. 0. This flaw allows attackers to execute arbitrary scripts in the context of the user's browser and inject malicious HTML into web pages viewed by the user. The vulnerability has a CVSS 3. 0 base score of 6. 1, indicating medium severity. No official patch or remediation guidance has been provided yet, and there are no known exploits in the wild at this time.
AI Analysis
Technical Summary
CVE-2026-40451 is a cross-site scripting vulnerability affecting DeepL's Chrome browser extension versions 1.22.0 to 1.23.0. The vulnerability enables an attacker to execute arbitrary JavaScript code within the user's browser session and inject malicious HTML content into web pages the user visits. This can lead to limited confidentiality and integrity impacts, such as theft of sensitive information or manipulation of displayed content. The vulnerability is remotely exploitable without privileges but requires user interaction. The CVSS 3.0 vector is AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N, reflecting network attack vector, low attack complexity, no privileges required, user interaction required, scope changed, and low confidentiality and integrity impacts with no availability impact. No official fix or patch has been disclosed by the vendor as of the published date.
Potential Impact
Successful exploitation allows attackers to execute arbitrary scripts in the user's browser context and inject malicious HTML into web pages, potentially leading to theft of sensitive information or manipulation of content. The impact is limited to confidentiality and integrity with no direct availability impact. The vulnerability requires user interaction and affects only specific extension versions. There are no known active exploits reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, users should consider disabling or uninstalling the affected DeepL Chrome extension versions 1.22.0 through 1.23.0 to avoid exposure. Monitor official DeepL communications for updates and apply any released patches promptly.
CVE-2026-40451: Cross-site scripting (XSS) in DeepL Chrome browser extension
Description
A cross-site scripting (XSS) vulnerability exists in the DeepL Chrome browser extension versions 1. 22. 0 through 1. 23. 0. This flaw allows attackers to execute arbitrary scripts in the context of the user's browser and inject malicious HTML into web pages viewed by the user. The vulnerability has a CVSS 3. 0 base score of 6. 1, indicating medium severity. No official patch or remediation guidance has been provided yet, and there are no known exploits in the wild at this time.
CVSS v3.0
Score 6.1medium
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-40451 is a cross-site scripting vulnerability affecting DeepL's Chrome browser extension versions 1.22.0 to 1.23.0. The vulnerability enables an attacker to execute arbitrary JavaScript code within the user's browser session and inject malicious HTML content into web pages the user visits. This can lead to limited confidentiality and integrity impacts, such as theft of sensitive information or manipulation of displayed content. The vulnerability is remotely exploitable without privileges but requires user interaction. The CVSS 3.0 vector is AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N, reflecting network attack vector, low attack complexity, no privileges required, user interaction required, scope changed, and low confidentiality and integrity impacts with no availability impact. No official fix or patch has been disclosed by the vendor as of the published date.
Potential Impact
Successful exploitation allows attackers to execute arbitrary scripts in the user's browser context and inject malicious HTML into web pages, potentially leading to theft of sensitive information or manipulation of content. The impact is limited to confidentiality and integrity with no direct availability impact. The vulnerability requires user interaction and affects only specific extension versions. There are no known active exploits reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, users should consider disabling or uninstalling the affected DeepL Chrome extension versions 1.22.0 through 1.23.0 to avoid exposure. Monitor official DeepL communications for updates and apply any released patches promptly.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- jpcert
- Date Reserved
- 2026-04-13T06:27:03.647Z
- Cvss Version
- 3.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69e85dc119fe3cd2cd708088
Added to database: 4/22/2026, 5:33:53 AM
Last enriched: 4/29/2026, 11:45:45 AM
Last updated: 6/6/2026, 10:55:29 PM
Views: 62
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