GCHQ CyberChef up to 10.x Show Base64 Offsets /#recipe cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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5.6$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in GCHQ CyberChef up to 10.x. Affected by this vulnerability is an unknown functionality of the file /#recipe of the component Show Base64 Offsets. The manipulation results in cross site scripting. This vulnerability is identified as CVE-2026-42615. The attack can be executed remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in GCHQ CyberChef up to 10.x. It has been classified as problematic. Affected is some unknown functionality of the file /#recipe of the component Show Base64 Offsets. The manipulation with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as 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. This is going to have an impact on integrity. CVE summarizes:

GCHQ CyberChef before 11.0.0 allows XSS via Show Base64 offsets, as demonstrated by the /#recipe=Show_Base64_offsets('%3Cscript substring.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-42615 since 04/29/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. 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 11.0.0 eliminates this vulnerability.

The vulnerability is also documented in the databases at CNNVD (CNNVD-202604-5698) and EUVD (EUVD-2026-26191). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.7
VulDB Meta Temp Score: 5.6

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

CNA Base Score: 7.2
CNA Vector (MITRE): 🔒

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: CyberChef 11.0.0

Timelineinfo

04/29/2026 Advisory disclosed
04/29/2026 +0 days CVE reserved
04/29/2026 +0 days VulDB entry created
05/06/2026 +7 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-42615 (🔒)
GCVE (CVE): GCVE-0-2026-42615
GCVE (VulDB): GCVE-100-360096
EUVD: 🔒
CNNVD: CNNVD-202604-5698 - CyberChef 跨站脚本漏洞

Entryinfo

Created: 04/29/2026 05:59
Updated: 05/06/2026 18:01
Changes: 04/29/2026 05:59 (65), 04/29/2026 08:10 (1), 04/30/2026 15:18 (6), 05/01/2026 19:01 (1), 05/02/2026 22:28 (1), 05/03/2026 16:59 (1), 05/04/2026 23:49 (1), 05/05/2026 18:42 (1), 05/06/2026 18:01 (1)
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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