SiteGround Speed Optimizer Plugin up to 7.8.0 on WordPress 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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4.9$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in SiteGround Speed Optimizer Plugin up to 7.8.0. This vulnerability affects unknown code. The manipulation results in cross site scripting. This vulnerability is reported as CVE-2026-15421. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability classified as problematic has been found in SiteGround Speed Optimizer Plugin up to 7.8.0. Affected is an unknown part. 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:

The Speed Optimizer – The All-In-One Performance-Boosting Plugin plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Image Tag Attributes in all versions up to, and including, 7.8.0 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This is only exploitable when the site administrator has enabled the Lazy Load Media option in the plugin settings.

The advisory is shared for download at wordfence.com. This vulnerability is traded as CVE-2026-15421 since 07/10/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1059.007.

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

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.9
VulDB Meta Temp Score: 4.9

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

CNA Base Score: 6.4
CNA Vector (Wordfence): 🔒

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
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

07/10/2026 CVE reserved
08/19/2026 +40 days Advisory disclosed
08/19/2026 +0 days VulDB entry created
08/19/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: wordfence.com
Status: Not defined

CVE: CVE-2026-15421 (🔒)
GCVE (CVE): GCVE-0-2026-15421
GCVE (VulDB): GCVE-100-392472

Entryinfo

Created: 08/19/2026 04:10
Changes: 08/19/2026 04:10 (62)
Complete: 🔍
Cache ID: 216::103

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