CVE-2025-52892Network attack vector

Authenticated service denial via double-slash router cache corruption

Published Aug 5, 2025 · Updated Aug 5, 2025

Router-cache denial of service in EspoCRM 9.1.6 and earlier allows remote authenticated users to halt the instance via a double-slash URI. The API starter passes a request path beginning with // to Slim after route-cache setup, allowing Slim to corrupt the shared router cache instead of rejecting the malformed path. Exploitation requires a highly privileged user to load the crafted URL and a web server that preserves the leading double slash; service remains unavailable until the cache is rebuilt.

CVSS severity4.5
Medium
EPSS probability0.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Router-cache denial of service in EspoCRM 9.1.6 and earlier allows remote authenticated users to halt the instance via a double-slash URI. The API starter passes a request path beginning with // to Slim after route-cache setup, allowing Slim to corrupt the shared router cache instead of rejecting the malformed path. Exploitation requires a highly privileged user to load the crafted URL and a web server that preserves the leading double slash; service remains unavailable until the cache is rebuilt.

The record

CVE
CVE-2025-52892
Published
Aug 5, 2025
Updated
Aug 5, 2025
Vendor
EspoCRM
Product
EspoCRM
Classifications
CWE-444, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 5, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 9.1.7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

EspoCRM · EspoCRMversion=< 9.1.7

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
4.5GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-444Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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