CVE-2026-55495: Cloudreve is a self-hosted file management and sharing system. Prior to 4.17.0, the WOPI PUT_RELATIVE handler passes X-WOPI-SuggestedTarget to URI.JoinRaw as a path rather than a f

mediumCVSS 4.3CVE-2026-55495

Cloudreve is a self-hosted file management and sharing system. Prior to 4.17.0, the WOPI PUT_RELATIVE handler passes X-WOPI-SuggestedTarget to URI.JoinRaw as a path rather than a filename, allowing slash and dot-dot segments to escape the source file directory and create or conditionally overwrite files elsewhere in the same owner account. This issue is fixed in version 4.17.0.

Details

Source: NVD Recent CVEs (US · database · site)
Severity: medium — CVSS 4.3
Published: 2026-07-31
Last updated: 2026-07-31
Exploitation: Not in CISA KEV at last sync

Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-55495

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-554950.38% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 30% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-55495	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

mediumGHSA-49h3-cwhj-4737: Cloudreve: Path Traversal in WOPI PUT_RELATIVE Allows Arbitrary File Creation in Owner Ac…ghsa

Recent advisories for Cloudreve is a

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

mediumCVE-2026-62323: Cloudreve is a self-hosted file management and sharing system. Prior to 4.17.0, ViewerSessionV…nvd · 2026-07-31
highCVE-2026-55502: Cloudreve is a self-hosted file management and sharing system. Prior to 4.17.0, POST /api/v4/a…nvd · 2026-07-31
mediumCVE-2026-55499: Cloudreve is a self-hosted file management and sharing system. Prior to 4.17.0, a single-file …nvd · 2026-07-31
mediumCVE-2026-55497: Cloudreve is a self-hosted file management and sharing system. Prior to 4.17.0, the built-in t…nvd · 2026-07-31
mediumCVE-2026-55496: Cloudreve is a self-hosted file management and sharing system. Prior to 4.17.0, GET /api/v4/us…nvd · 2026-07-31
mediumGHSA-v6w6-358x-2433: Cloudreve Admin.Read OAuth tokens can trigger server-side node test requestsghsa · 2026-07-24