PHP League CommonMark library up to 0.18.0 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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A vulnerability was found in PHP League CommonMark library up to 0.18.0 (Software Library). It has been rated as problematic. Affected by this issue is an unknown code block. 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:

Cross-site scripting (XSS) vulnerability in the PHP League CommonMark library versions 0.15.6 through 0.18.x before 0.18.1 allows remote attackers to insert unsafe URLs into HTML (even if allow_unsafe_links is false) via a newline character (e.g., writing javascript as javascri%0apt).

The bug was discovered 12/29/2018. The weakness was released 12/30/2018 (Website). The advisory is available at This vulnerability is handled as CVE-2018-20583 since 12/29/2018. The attack may be launched remotely. No form of authentication is required for exploitation. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1059.007 by the MITRE ATT&CK project.

The vulnerability was handled as a non-public zero-day exploit for at least 1 days. During that time the estimated underground price was around $0-$5k.

Upgrading to version 0.18.1 eliminates this vulnerability.

Entries connected to this vulnerability are available at VDB-134518, VDB-138322, VDB-184425 and VDB-205146.







CPE 2.3info

CPE 2.2info


VulDB CVSS-B Score: 🔍
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VulDB Meta Base Score: 5.7
VulDB Meta Temp Score: 5.6

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.1
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Class: Cross site scripting
CWE: CWE-79 / CWE-74 / CWE-707

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍


Threat Intelligenceinfo

Interest: 🔍
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Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: CommonMark library 0.18.1


12/29/2018 🔍
12/29/2018 +0 days 🔍
12/30/2018 +1 days 🔍
12/30/2018 +0 days 🔍
12/30/2018 +0 days 🔍
06/22/2023 +1635 days 🔍


Advisory: 337
Status: Not defined

CVE: CVE-2018-20583 (🔍)
See also: 🔍


Created: 12/30/2018 05:58 PM
Updated: 06/22/2023 02:11 PM
Changes: 12/30/2018 05:58 PM (58), 04/25/2020 09:58 AM (1), 06/22/2023 02:11 PM (5)
Complete: 🔍
Cache ID: 34:DC8:40


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