{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-53791", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-06-10T20:14:32.827Z", "datePublished": "2026-08-13T14:38:10.300Z", "dateUpdated": "2026-08-14T18:09:56.975Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-08-14T16:50:09.199Z" }, "title": "rsync < 3.5.0 Daemon IP Spoofing via PROXY Protocol Header", "datePublic": "2026-08-12T00:00:00.000Z", "problemTypes": [ { "descriptions": [ { "lang": "en", "cweId": "CWE-290", "description": "CWE-290 Authentication Bypass by Spoofing", "type": "CWE" } ] } ], "affected": [ { "vendor": "RsyncProject", "product": "rsync", "repo": "https://github.com/RsyncProject/rsync", "versions": [ { "status": "affected", "version": "0", "lessThanOrEqual": "3.4.4", "versionType": "semver" }, { "status": "unaffected", "version": "3.5.0", "versionType": "semver" } ], "defaultStatus": "unaffected", "packageURL": "pkg:github/RsyncProject/rsync" } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:a:samba:rsync:*:*:*:*:*:*:*:*", "versionEndIncluding": "3.4.4" } ] } ] } ], "descriptions": [ { "lang": "en", "value": "rsync daemon before 3.5.0 contains an IP address spoofing vulnerability that allows unauthenticated remote attackers to bypass IP-based access controls by sending a crafted PROXY protocol header with a forged source address. Attackers who can connect directly to the rsync daemon can inject a spoofed source IP in the PROXY protocol header to circumvent hosts allow/deny rules, gaining unauthorized access that would otherwise be blocked based on their real source address.", "supportingMedia": [ { "type": "text/html", "base64": false, "value": "

rsync daemon before 3.5.0 contains an IP address spoofing vulnerability that allows unauthenticated remote attackers to bypass IP-based access controls by sending a crafted PROXY protocol header with a forged source address. Attackers who can connect directly to the rsync daemon can inject a spoofed source IP in the PROXY protocol header to circumvent hosts allow/deny rules, gaining unauthorized access that would otherwise be blocked based on their real source address.

" } ] } ], "references": [ { "url": "https://github.com/RsyncProject/rsync/security/advisories/GHSA-h2q9-5fr8-w635", "name": "GitHub Security Advisory (GHSA-h2q9-5fr8-w635)", "tags": [ "vendor-advisory" ] }, { "url": "https://github.com/RsyncProject/rsync/releases/tag/v3.5.0", "name": "rsync 3.5.0 Release Notes", "tags": [ "release-notes" ] }, { "url": "https://www.vulncheck.com/advisories/rsync-daemon-ip-spoofing-via-proxy-protocol-header", "tags": [ "third-party-advisory" ] } ], "metrics": [ { "format": "CVSS", "scenarios": [ { "lang": "en", "value": "GENERAL" } ], "cvssV4_0": { "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "subConfidentialityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "subIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "version": "4.0", "baseSeverity": "CRITICAL", "baseScore": 9.1, "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N" } }, { "format": "CVSS", "scenarios": [ { "lang": "en", "value": "GENERAL" } ], "cvssV3_1": { "version": "3.1", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "NONE", "baseSeverity": "CRITICAL", "baseScore": 9.1, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N" } } ], "source": { "discovery": "INTERNAL" }, "x_generator": { "engine": "Vulnogram 1.0.4" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2026-08-14T18:02:57.002288Z", "id": "CVE-2026-53791", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-08-14T18:09:56.975Z" } } ] } }