MarkUsProject Markus up to 2.9.0 html_content 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 was found in MarkUsProject Markus up to 2.9.0. It has been rated as problematic. The impacted element is an unknown function of the file courses//assignments//submissions/html_content. This manipulation causes cross site scripting. The identification of this vulnerability is CVE-2026-28405. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in MarkUsProject Markus up to 2.9.0. It has been declared as problematic. Affected by this vulnerability is an unknown function of the file courses//assignments//submissions/html_content. The manipulation with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect integrity. The summary by CVE is:

MarkUs is a web application for the submission and grading of student assignments. Prior to version 2.9.1, the courses/<:course_id>/assignments/<:assignment_id>/submissions/html_content route reads the contents of a student-submitted file and renders them without sanitization. This issue has been patched in version 2.9.1.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-28405 since 02/27/2026. The exploitation appears to be easy. The attack can be launched remotely. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

Upgrading to version 2.9.1 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 55d74f2ddb72d2ec2f29aa2b4cb6b2da10755036 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

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

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

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

NVD Base Score: 5.4
NVD Vector: 🔒

CNA Base Score: 8.0
CNA Vector (GitHub_M): 🔒

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: Markus 2.9.1
Patch: 55d74f2ddb72d2ec2f29aa2b4cb6b2da10755036

Timelineinfo

02/27/2026 CVE reserved
03/06/2026 +7 days Advisory disclosed
03/06/2026 +0 days VulDB entry created
03/11/2026 +5 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-p5pc-pxrj-3893
Status: Confirmed

CVE: CVE-2026-28405 (🔒)
GCVE (CVE): GCVE-0-2026-28405
GCVE (VulDB): GCVE-100-349279

Entryinfo

Created: 03/06/2026 06:31
Updated: 03/11/2026 22:38
Changes: 03/06/2026 06:31 (69), 03/10/2026 13:32 (2), 03/11/2026 22:38 (11)
Complete: 🔍
Cache ID: 216::103

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