CVE-2026-52780

Remote code execution via cache store poisoning

Published Jun 26, 2026 · Updated Jun 26, 2026

Cache store poisoning in OpenProject before 17.3.3 and OpenProject 17.4.0 allows remote attackers to execute code on the server. The upstream advisory does not disclose the affected cache key or store operation, the attacker-controlled input, or how cached data reaches execution. Exploitation requires unauthenticated adjacent-network access and can expose or modify application data and interrupt service.

CVSS severity9.6
Critical
EPSS probability0.39%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cache store poisoning in OpenProject before 17.3.3 and OpenProject 17.4.0 allows remote attackers to execute code on the server. The upstream advisory does not disclose the affected cache key or store operation, the attacker-controlled input, or how cached data reaches execution. Exploitation requires unauthenticated adjacent-network access and can expose or modify application data and interrupt service.

The record

CVE
CVE-2026-52780
Published
Jun 26, 2026
Updated
Jun 26, 2026
Vendor
OpenProject GmbH
Product
OpenProject
Classifications
CWE-20, T1190
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 26, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 26, 2026Record 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=< 17.3.3
  2. Affected versionversion=>= 17.4.0, < 17.4.1

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

OpenProject GmbH · OpenProjectversion=< 17.3.3; version=>= 17.4.0, < 17.4.1

Published CVSS scores

9.6GitHub, Inc.CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/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.

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No observations available

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

Weakness, pattern, technique

CWE-20Improper Input Validation
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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