CVE-2026-55499: cloudreve Incorrect Authorization
Vulnerability summary
CVE-2026-55499 is a medium (CVSS 4.3) Incorrect Authorization vulnerability in cloudreve. EPSS estimates a 0.33% chance of exploitation in the next 30 days, higher than 24.9% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 2 · Related 2Timeline
- 31-07-2026PublishedVulnerability first disclosed.
- 31-07-2026Last modifiedVulnerability information updated.
Description
Cloudreve is a self-hosted file management and sharing system. Prior to 4.17.0, a single-file share event-stream subscription resolves the share root to the owner’s parent folder and subscribes to that folder topic, allowing an authenticated share recipient to receive names, paths, rename targets, event types, and hashed identifiers for unshared sibling files and folders. This issue is fixed in version 4.17.0.
CVSS metrics
3 scores · 3 sources · 1 version- OSV · GoEcosystem advisory · calculated4.3MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
- NVDNIST4.3MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
EPSS trend
Probability
0.33%
Chance of exploitation in the next 30 days
Percentile
25%
Versus all other CVEs
30-day change
+0.09 pp
From 0.24% on 21-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Github.com/cloudreve/Cloudreve2 products
- v3≤ 3.0.0-20250225100611-da4e44b77af4 | All versions (No fix recorded)
- v4< 4.0.0-20260613030215-0b00dd308f13
Cloudreve1 product
- cloudreve< 4.17.0
Github.com/cloudreve1 product
- CloudreveAll versions (No fix recorded)
3 vendors · 4 products
References
4 links- github.com/cloudreve/cloudreve/security/advisories/GHSA-w8x7-h2px-xmq8X Refsource CONFIRMWEBAdvisory