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CVE-2026-53794

Full vulnerability record from the local CVENow database.

Description

rsync before 3.5.0 contains a logic error in --max-alloc handling that allows a sender or configuration setting --max-alloc=0 to disable allocation sanity checks entirely rather than enforcing a zero-byte cap. Attackers can exploit this flaw to cause the receiver to attempt unbounded memory allocations for file list and data structures, potentially exhausting available memory and causing a denial of service.

Severity
MEDIUM
CVSS score
6.9 (v4.0)
Vulnerability status
Awaiting Analysis
Source identifier
Published
2026-08-13 15:19:43.853000
Last modified
2026-10-24 16:10:00.153000
View original CVE JSON
{
  "id": "CVE-2026-53794",
  "sourceIdentifier": "[email protected]",
  "published": "2026-08-13T15:19:43.853",
  "lastModified": "2026-10-24T16:10:00.153",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "rsync before 3.5.0 contains a logic error in --max-alloc handling that allows a sender or configuration setting --max-alloc=0 to disable allocation sanity checks entirely rather than enforcing a zero-byte cap. Attackers can exploit this flaw to cause the receiver to attempt unbounded memory allocations for file list and data structures, potentially exhausting available memory and causing a denial of service."
    },
    {
      "lang": "es",
      "value": "rsync anterior a la versión 3.5.0 contiene un error lógico en el manejo de --max-alloc que permite que un remitente o una configuración que establece --max-alloc=0 desactive por completo las comprobaciones de cordura de asignación en lugar de imponer un límite de cero bytes. Los atacantes pueden explotar esta falla para hacer que el receptor intente asignaciones de memoria ilimitadas para la lista de archivos y las estructuras de datos, agotando potencialmente la memoria disponible y causando una denegación de servicio."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "RsyncProject",
          "product": "rsync",
          "defaultStatus": "unaffected",
          "repo": "https://github.com/RsyncProject/rsync",
          "packageURL": "pkg:github/RsyncProject/rsync",
          "versions": [
            {
              "version": "0",
              "lessThanOrEqual": "3.4.4",
              "versionType": "semver",
              "status": "affected"
            },
            {
              "version": "3.5.0",
              "versionType": "semver",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "baseScore": 6.9,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "NONE",
          "vulnAvailabilityImpact": "LOW",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "LOW"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-08-13T15:34:23.072313Z",
          "id": "CVE-2026-53794",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-1284"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/RsyncProject/rsync/releases/tag/v3.5.0",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/RsyncProject/rsync/security/advisories/GHSA-p827-vwcp-m964",
      "source": "[email protected]"
    },
    {
      "url": "https://www.vulncheck.com/advisories/rsync-denial-of-service-via-max-alloc-0-logic-error",
      "source": "[email protected]"
    }
  ]
}