CVE-2026-15709

Full vulnerability record from the local CVENow database.
Description

A flaw was found in libsoup's WebSocket implementation when using the permessage-deflate extension. The extension's decompression loop (inflate()) processes data in chunks without enforcing an upper boundary limit on the output buffer size. While libsoup limits the incoming compressed frame size via max_incoming_payload_size, it fails to track or limit memory allocation during decompression. A separate check for decompressed size (max_total_message_size) exists but executes only after inflation is complete, and it is entirely disabled by default for client connections. A remote, unauthenticated attacker can exploit this by sending a small, highly compressed payload (a decompression bomb), causing unbounded memory allocation that triggers an Out-of-Memory (OOM) crash and a Denial of Service (DoS).
Severity
HIGH
CVSS score
7.5 (v3.1)
Vulnerability status
Deferred
Source identifier
[email protected]
Published
2026-07-14 20:16:57.027000
Last modified
2026-11-05 17:18:09.810000
View original CVE JSON
{
  "id": "CVE-2026-15709",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-14T20:16:57.027",
  "lastModified": "2026-11-05T17:18:09.810",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A flaw was found in libsoup's WebSocket implementation when using the permessage-deflate extension. The extension's decompression loop (inflate()) processes data in chunks without enforcing an upper boundary limit on the output buffer size. While libsoup limits the incoming compressed frame size via max_incoming_payload_size, it fails to track or limit memory allocation during decompression. A separate check for decompressed size (max_total_message_size) exists but executes only after inflation is complete, and it is entirely disabled by default for client connections. A remote, unauthenticated attacker can exploit this by sending a small, highly compressed payload (a decompression bomb), causing unbounded memory allocation that triggers an Out-of-Memory (OOM) crash and a Denial of Service (DoS)."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 10",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup3",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:10.2"
          ],
          "versions": [
            {
              "version": "0:3.6.5-3.el10_2.14",
              "lessThan": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 10.0 Extended Update Support",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup3",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux_eus:10.0"
          ],
          "versions": [
            {
              "version": "0:3.6.5-3.el10_0.17",
              "lessThan": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/a:redhat:rhel_aus:8.4::appstream",
            "cpe:/a:redhat:rhel_eus_long_life:8.4::appstream",
            "cpe:/o:redhat:rhel_aus:8.4::baseos",
            "cpe:/o:redhat:rhel_eus_long_life:8.4::baseos"
          ],
          "versions": [
            {
              "version": "0:2.62.3-2.el8_4.10",
              "lessThan": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/a:redhat:rhel_aus:8.4::appstream",
            "cpe:/a:redhat:rhel_eus_long_life:8.4::appstream",
            "cpe:/o:redhat:rhel_aus:8.4::baseos",
            "cpe:/o:redhat:rhel_eus_long_life:8.4::baseos"
          ],
          "versions": [
            {
              "version": "0:2.62.3-2.el8_4.10",
              "lessThan": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/a:redhat:rhel_aus:8.6::appstream",
            "cpe:/a:redhat:rhel_eus_long_life:8.6::appstream",
            "cpe:/o:redhat:rhel_aus:8.6::baseos",
            "cpe:/o:redhat:rhel_eus_long_life:8.6::baseos"
          ],
          "versions": [
            {
              "version": "0:2.62.3-2.el8_6.10",
              "lessThan": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/a:redhat:rhel_aus:8.6::appstream",
            "cpe:/a:redhat:rhel_eus_long_life:8.6::appstream",
            "cpe:/o:redhat:rhel_aus:8.6::baseos",
            "cpe:/o:redhat:rhel_eus_long_life:8.6::baseos"
          ],
          "versions": [
            {
              "version": "0:2.62.3-2.el8_6.10",
              "lessThan": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 8.8 Telecommunications Update Service",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/a:redhat:rhel_e4s:8.8::appstream",
            "cpe:/a:redhat:rhel_tus:8.8::appstream",
            "cpe:/o:redhat:rhel_e4s:8.8::baseos",
            "cpe:/o:redhat:rhel_tus:8.8::baseos"
          ],
          "versions": [
            {
              "version": "0:2.62.3-3.el8_8.11",
              "lessThan": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/a:redhat:rhel_e4s:8.8::appstream",
            "cpe:/a:redhat:rhel_tus:8.8::appstream",
            "cpe:/o:redhat:rhel_e4s:8.8::baseos",
            "cpe:/o:redhat:rhel_tus:8.8::baseos"
          ],
          "versions": [
            {
              "version": "0:2.62.3-3.el8_8.11",
              "lessThan": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 9",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/a:redhat:enterprise_linux:9::appstream"
          ],
          "versions": [
            {
              "version": "0:2.72.0-16.el9_8.3",
              "lessThan": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/a:redhat:rhel_e4s:9.2::appstream"
          ],
          "versions": [
            {
              "version": "0:2.72.0-8.el9_2.13",
              "lessThan": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/a:redhat:rhel_e4s:9.4::appstream"
          ],
          "versions": [
            {
              "version": "0:2.72.0-8.el9_4.12",
              "lessThan": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 9.6 Extended Update Support",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/a:redhat:rhel_eus:9.6::appstream"
          ],
          "versions": [
            {
              "version": "0:2.72.0-10.el9_6.9",
              "lessThan": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 6",
          "defaultStatus": "unknown",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/o:redhat:rhel_els:6"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 7",
          "defaultStatus": "unknown",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/o:redhat:rhel_els:7"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 8",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/a:redhat:enterprise_linux:8"
          ]
        }
      ]
    }
  ],
  "metrics": {
    "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:H",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-15T12:58:14.451474Z",
          "id": "CVE-2026-15709",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-409"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://access.redhat.com/errata/RHSA-2026:68234",
      "source": "[email protected]"
    },
    {
      "url": "https://access.redhat.com/errata/RHSA-2026:68235",
      "source": "[email protected]"
    },
    {
      "url": "https://access.redhat.com/errata/RHSA-2026:68612",
      "source": "[email protected]"
    },
    {
      "url": "https://access.redhat.com/errata/RHSA-2026:69108",
      "source": "[email protected]"
    },
    {
      "url": "https://access.redhat.com/errata/RHSA-2026:69297",
      "source": "[email protected]"
    },
    {
      "url": "https://access.redhat.com/errata/RHSA-2026:69863",
      "source": "[email protected]"
    },
    {
      "url": "https://access.redhat.com/errata/RHSA-2026:70598",
      "source": "[email protected]"
    },
    {
      "url": "https://access.redhat.com/errata/RHSA-2026:70599",
      "source": "[email protected]"
    },
    {
      "url": "https://access.redhat.com/errata/RHSA-2026:71389",
      "source": "[email protected]"
    },
    {
      "url": "https://access.redhat.com/security/cve/CVE-2026-15709",
      "source": "[email protected]"
    },
    {
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2499922",
      "source": "[email protected]"
    },
    {
      "url": "https://gitlab.gnome.org/GNOME/libsoup/-/issues/511",
      "source": "[email protected]"
    },
    {
      "url": "https://gitlab.gnome.org/GNOME/libsoup/-/issues/511",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ]
}