{
  "document": {
    "aggregate_severity": {
      "text": "Important"
    },
    "category": "csaf_security_advisory",
    "csaf_version": "2.0",
    "distribution": {
      "text": "TuxCare License Agreement",
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "en",
    "notes": [
      {
        "category": "legal_disclaimer",
        "text": "This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Cloud Linux Inc. and provide a link to the original.",
        "title": "Terms of Use"
      },
      {
        "category": "details",
        "text": "* SECURITY UPDATE: integer overflow in compressed-token decoder\n     - debian/patches/CVE-2026-43618.patch: cap rx_token at MAX_TOKEN_INDEX\n       and reject over-long simple_recv_token literal chunks to prevent\n       remote memory disclosure via crafted compressed stream\n     - CVE-2026-43618",
        "title": "Details"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "https://tuxcare.com/contact/",
      "name": "TuxCare",
      "namespace": "https://tuxcare.com/"
    },
    "references": [
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        "category": "self",
        "summary": "https://cve.tuxcare.com/els/releases/CLSA-2026:1779368965",
        "url": "https://cve.tuxcare.com/els/releases/CLSA-2026:1779368965"
      },
      {
        "category": "self",
        "summary": "Canonical URL",
        "url": "https://security.tuxcare.com/csaf/v2/els_os/ubuntu16.04els/advisories/2026/clsa-2026_1779368965.json"
      }
    ],
    "tracking": {
      "current_release_date": "2026-05-21T13:10:00Z",
      "generator": {
        "date": "2026-05-21T13:10:00Z",
        "engine": {
          "name": "pyCSAF"
        }
      },
      "id": "CLSA-2026:1779368965",
      "initial_release_date": "2026-05-21T13:10:00Z",
      "revision_history": [
        {
          "date": "2026-05-21T13:10:00Z",
          "number": "1",
          "summary": "Initial version"
        }
      ],
      "status": "final",
      "version": "1"
    },
    "title": "Fix CVE(s): CVE-2026-43618"
  },
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                "product": {
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                  "product_id": "Ubuntu-16",
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            "name": "Ubuntu"
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        "category": "vendor",
        "name": "Canonical Ltd."
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        "relates_to_product_reference": "Ubuntu-16"
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  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-43618",
      "cwe": {
        "id": "CWE-125",
        "name": "Out-of-bounds Read"
      },
      "notes": [
        {
          "category": "description",
          "text": "Rsync version 3.4.2 and prior contain an integer overflow vulnerability in the compressed-token decoder where a 32-bit signed counter is not checked for overflow, allowing a malicious sender to trigger an overflow that causes the receiver process to read and return data from outside the intended buffer bounds. Attackers can exploit this vulnerability to disclose process memory contents including environment variables, passwords, heap and stack data, and library memory pointers, significantly reducing ASLR effectiveness and facilitating further exploitation.",
          "title": "Vulnerability description"
        },
        {
          "category": "general",
          "text": "The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.",
          "title": "CVSS score applicability"
        }
      ],
      "product_status": {
        "fixed": [
          "Ubuntu-16:rsync-0:3.1.1-3ubuntu1.3+tuxcare.els8.amd64"
        ],
        "known_affected": [
          "Ubuntu-16:rsync-0:3.1.1-3ubuntu1.3+tuxcare.els1.amd64",
          "Ubuntu-16:rsync-0:3.1.1-3ubuntu1.3+tuxcare.els2.amd64",
          "Ubuntu-16:rsync-0:3.1.1-3ubuntu1.3+tuxcare.els4.amd64",
          "Ubuntu-16:rsync-0:3.1.1-3ubuntu1.3+tuxcare.els5.amd64",
          "Ubuntu-16:rsync-0:3.1.1-3ubuntu1.3+tuxcare.els6.amd64",
          "Ubuntu-16:rsync-0:3.1.1-3ubuntu1.3+tuxcare.els7.amd64"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "Canonical URL",
          "url": "https://cve.tuxcare.com/els/cve/CVE-2026-43618"
        },
        {
          "category": "external",
          "summary": "https://github.com/RsyncProject/rsync/releases/tag/v3.4.3",
          "url": "https://github.com/RsyncProject/rsync/releases/tag/v3.4.3"
        },
        {
          "category": "external",
          "summary": "https://github.com/RsyncProject/rsync/security/advisories/GHSA-g37v-g3gj-pmwq",
          "url": "https://github.com/RsyncProject/rsync/security/advisories/GHSA-g37v-g3gj-pmwq"
        },
        {
          "category": "external",
          "summary": "https://www.vulncheck.com/advisories/rsync-integer-overflow-information-disclosure",
          "url": "https://www.vulncheck.com/advisories/rsync-integer-overflow-information-disclosure"
        }
      ],
      "release_date": "2026-05-20T02:16:00Z",
      "remediations": [
        {
          "category": "vendor_fix",
          "date": "2026-05-21T13:09:28.192208Z",
          "details": "Details on how to apply the fix are available at: https://cve.tuxcare.com/els/releases/CLSA-2026:1779368965",
          "product_ids": [
            "Ubuntu-16:rsync-0:3.1.1-3ubuntu1.3+tuxcare.els8.amd64"
          ],
          "url": "https://cve.tuxcare.com/els/releases/CLSA-2026:1779368965"
        },
        {
          "category": "none_available",
          "date": "2026-05-20T02:16:00Z",
          "details": "Affected",
          "product_ids": [
            "Ubuntu-16:rsync-0:3.1.1-3ubuntu1.3+tuxcare.els1.amd64",
            "Ubuntu-16:rsync-0:3.1.1-3ubuntu1.3+tuxcare.els2.amd64",
            "Ubuntu-16:rsync-0:3.1.1-3ubuntu1.3+tuxcare.els4.amd64",
            "Ubuntu-16:rsync-0:3.1.1-3ubuntu1.3+tuxcare.els5.amd64",
            "Ubuntu-16:rsync-0:3.1.1-3ubuntu1.3+tuxcare.els6.amd64",
            "Ubuntu-16:rsync-0:3.1.1-3ubuntu1.3+tuxcare.els7.amd64"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 8.1,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
            "version": "3.1"
          },
          "products": [
            "Ubuntu-16:rsync-0:3.1.1-3ubuntu1.3+tuxcare.els8.amd64"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "details": "Important"
        }
      ]
    }
  ]
}