OpenLiteSpeed 1.7.9 Notes cross site scripting

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.2$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in OpenLiteSpeed 1.7.9. Affected by this vulnerability is an unknown functionality. This manipulation of the argument Notes causes cross site scripting. The identification of this vulnerability is CVE-2021-47855. It is possible to initiate the attack remotely. Furthermore, there is an exploit available.

Detailsinfo

A vulnerability classified as problematic was found in OpenLiteSpeed 1.7.9. Affected by this vulnerability is an unknown code. The manipulation of the argument Notes 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:

Openlitespeed 1.7.9 contains a stored cross-site scripting vulnerability in the dashboard's Notes parameter that allows administrators to inject malicious scripts. Attackers can craft a payload in the Notes field during listener configuration that will execute when an administrator clicks on the Default Icon.

The weakness was shared by cmOs as 49727. It is possible to read the advisory at exploit-db.com. This vulnerability is known as CVE-2021-47855 since 01/14/2026. 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 and also a public exploit are known. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

It is possible to download the exploit at exploit-db.com. It is declared as proof-of-concept.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Exploit-DB (49727). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 3.5
VulDB Temp Score: 3.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

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

CVSSv2info

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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: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Exploit-DB: 🔒

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

01/14/2026 CVE reserved
01/21/2026 +7 days Advisory disclosed
01/21/2026 +0 days VulDB entry created
01/21/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: 49727
Researcher: cmOs
Status: Not defined

CVE: CVE-2021-47855 (🔒)
GCVE (CVE): GCVE-0-2021-47855
GCVE (VulDB): GCVE-100-342199
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 01/21/2026 20:09
Changes: 01/21/2026 20:09 (79)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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