CVE-2026-17532
Seraphinite Accelerator <= 2.29.18 - Reflected Cross-Site Scripting
The Seraphinite Accelerator plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'seraph_accel_prep' parameter in versions up to, and including, 2.29.15. This is due to the CacheExtractPreparePageParams() function using PHP's loose inequality operator (!=) to compare the expected HMAC string against the JSON-decoded 'nonce' value — supplying the JSON boolean true causes any non-empty HMAC string to compare as loosely equal, bypassing the signature check — combined with insufficient output escaping in the _CbContentFinishSkip() function, which concatenates the attacker-controlled 'selfTest' field directly into the HTML response body. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a specially crafted link.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
6.1
Seraphinite Accelerator <= 2.29.18 - Reflected Cross-Site Scripting
The Seraphinite Accelerator plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'seraph_accel_prep' parameter in versions up to, and including, 2.29.15. This is due to the CacheExtractPreparePageParams() function using PHP's loose inequality operator (!=) to compare the expected HMAC string against the JSON-decoded 'nonce' value — supplying the JSON boolean true causes any non-empty HMAC string to compare as loosely equal, bypassing the signature check — combined with insufficient output escaping in the _CbContentFinishSkip() function, which concatenates the attacker-controlled 'selfTest' field directly into the HTML response body. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a specially crafted link.
- Record
CVE-2026-17532- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2026-53175
6.1
The Seraphinite Accelerator plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'seraph_accel_prep' parameter in versions up to, and including, 2.29.15. This is due to the CacheExtractPreparePageParams() function using PHP's loose inequality operator (!=) to compare the expected HMAC string against the JSON-decoded 'nonce' value — supplying the JSON boolean true causes any non-empty HMAC string to compare as loosely equal, bypassing the signature check — combined with insufficient output escaping in the _CbContentFinishSkip() function, which concatenates the attacker-controlled 'selfTest' field directly into the HTML response body. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a specially crafted link.
- Record
EUVD-2026-53175- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-ff83-hfr5-72ch
6.1
The Seraphinite Accelerator plugin for WordPress is vulnerable to Reflected Cross-Site Scripting...
The Seraphinite Accelerator plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'seraph_accel_prep' parameter in versions up to, and including, 2.29.15. This is due to the CacheExtractPreparePageParams() function using PHP's loose inequality operator (!=) to compare the expected HMAC string against the JSON-decoded 'nonce' value — supplying the JSON boolean true causes any non-empty HMAC string to compare as loosely equal, bypassing the signature check — combined with insufficient output escaping in the _CbContentFinishSkip() function, which concatenates the attacker-controlled 'selfTest' field directly into the HTML response body. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a specially crafted link.
- Record
GHSA-ff83-hfr5-72ch- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
6.1
The Seraphinite Accelerator plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the 'seraph_accel_prep' parameter in versions up to, and including, 2.29.15. This is due to the CacheExtractPreparePageParams() function using PHP's loose inequality operator (!=) to compare the expected HMAC string against the JSON-decoded 'nonce' value — supplying the JSON boolean true causes any non-empty HMAC string to compare as loosely equal, bypassing the signature check — combined with insufficient output escaping in the _CbContentFinishSkip() function, which concatenates the attacker-controlled 'selfTest' field directly into the HTML response body. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a specially crafted link.
- Record
CVE-2026-17532- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| Nuclei | Seraphinite Accelerator <= 2.29.18 - Cross-Site Scripting | |
| PoC in GitHub | kalhoralireza/CVE-2026-17532 | 2026-08-05 |
| PoC in GitHub | kalhoralireza/CVE-2026-17532-lab | 2026-08-25 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, Nuclei, NVD, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-17532 is a medium vulnerability (CVSS 6.1) in Seraphinitesoft Seraphinite Accelerator, published August 5, 2026. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 0.79%, the 56th percentile. No source names a fixed version.
References
wordfence.com/threat-intel/vulnerabilities/id/5aeea62b-bd6c-4fe2-8c0f-8c9919688e87?source=cve
plugins.trac.wordpress.org/browser/seraphinite-accelerator/tags/2.29.18/cache_ex.php
plugins.trac.wordpress.org/browser/seraphinite-accelerator/tags/2.29.18/common.php
plugins.trac.wordpress.org/browser/seraphinite-accelerator/tags/2.29.18/cache.php
plugins.trac.wordpress.org/browser/seraphinite-accelerator/tags/2.29.15/cache_ex.php
plugins.trac.wordpress.org/browser/seraphinite-accelerator/tags/2.29.15/common.php
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plugins.trac.wordpress.org/browser/seraphinite-accelerator/tags/2.29.15/cache.php
plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&new=3624461%40seraphinite-accelerator%2Ftrunk%2Fcommon.php&old=3619618%40seraphinite-accelerator%2Ftrunk%2Fcommon.php&sfp_email=&sfph_mail=
plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&new=3624461%40seraphinite-accelerator%2Ftrunk%2Fcache_ex.php&old=3619618%40seraphinite-accelerator%2Ftrunk%2Fcache_ex.php&sfp_email=&sfph_mail=
nvd.nist.gov/vuln/detail/CVE-2026-17532
github.com/advisories/GHSA-ff83-hfr5-72ch