MyBB 1.8.17 RSS Syndication class_feedgeneration.php XML Document 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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5.0$0-$5k0.00

Summaryinfo

A vulnerability was found in MyBB 1.8.17. It has been rated as problematic. Affected by this issue is some unknown functionality of the file inc/class_feedgeneration.php of the component RSS Syndication. Performing a manipulation as part of XML Document results in cross site scripting. This vulnerability was named CVE-2018-15596. The attack may be initiated remotely. In addition, an exploit is available.

Detailsinfo

A vulnerability was found in MyBB 1.8.17 (Content Management System). It has been classified as problematic. This affects an unknown function of the file inc/class_feedgeneration.php of the component RSS Syndication. The manipulation as part of a XML Document 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. The summary by CVE is:

An issue was discovered in inc/class_feedgeneration.php in MyBB 1.8.17. On the forum RSS Syndication page, one can generate a URL such as http://localhost/syndication.php?fid=&type=atom1.0&limit=15. The thread titles (within title elements of the generated XML documents) aren't sanitized, leading to XSS.

The bug was discovered 08/22/2018. The weakness was presented 08/28/2018 (Website). The advisory is shared at blog.mybb.com. This vulnerability is uniquely identified as CVE-2018-15596 since 08/20/2018. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Technical details and a public exploit are known. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

The exploit is shared for download at exploit-db.com. It is declared as proof-of-concept. The vulnerability was handled as a non-public zero-day exploit for at least 6 days. During that time the estimated underground price was around $5k-$25k. By approaching the search of inurl:inc/class_feedgeneration.php it is possible to find vulnerable targets with Google Hacking.

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 (45393). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.2
VulDB Meta Temp Score: 5.0

VulDB Base Score: 4.3
VulDB Temp Score: 3.9
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.1
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

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: 🔍
Google Hack: 🔍

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

08/20/2018 🔍
08/22/2018 +2 days 🔍
08/28/2018 +5 days 🔍
08/28/2018 +0 days 🔍
08/29/2018 +1 days 🔍
07/27/2025 +2524 days 🔍

Sourcesinfo

Product: mybb.com

Advisory: blog.mybb.com
Status: Not defined
Confirmation: 🔍

CVE: CVE-2018-15596 (🔍)
GCVE (CVE): GCVE-0-2018-15596
GCVE (VulDB): GCVE-100-123333
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 08/29/2018 08:26
Updated: 07/27/2025 23:29
Changes: 08/29/2018 08:26 (62), 03/18/2020 20:48 (5), 07/27/2025 23:29 (19)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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