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UBUNTU-CVE-2026-63075 (CVE-2026-63075)

Vulnerability from osv_ubuntu – Published: 2026-08-25 00:00 – Updated: 2026-09-16 11:36 – Source website
VLAI
Details

Issue summary: When OpenSSL processes QUIC traffic from a peer that repeatedly sends ack-eliciting packets while not acknowledging ACK-only responses, the QUIC stack can retain ACK-only packet metadata for the lifetime of the connection. Impact summary: A remote peer that can complete a QUIC handshake can cause connection-scoped memory growth which may lead to Denial of Service through memory exhaustion, especially with sustained traffic or many concurrent QUIC connections. CWE: CWE-770: Allocation of Resources Without Limits or Throttling Description: When the OpenSSL QUIC stack sends an ACK-only packet, there is no requirement by the QUIC protocol that the peer will acknowledge that ACK-only packet (i.e. it is itself not ack-eliciting). However, the OpenSSL implementation stores the metadata about the ACK frames regardless. In and of itself that's ok, but if a malicious peer establishes a connection, and then drives the connection such that ACK-only packets are forced from the OpenSSL implementation peer (i.e., by sending numerous PING frames), and then withholding any subsequent acks for ack-eliciting data, like legitimate data, said malicious peer can force inappropriate memory growth on the OpenSSL peer, potentially leading to a Denial of Service. The fix is to ensure that we account for the transmission of the ACK-only packet in the packet histories high and low watermark without actually storing the ACK-only packet metadata itself. FIPS impact: no The OpenSSL FIPS module is not affected as the QUIC code is outside the FIPS module boundary.

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
N/A (UNKNOWN)
low
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "nodejs",
            "binary_version": "4.2.6~dfsg-1ubuntu4.2+esm3"
          },
          {
            "binary_name": "nodejs-legacy",
            "binary_version": "4.2.6~dfsg-1ubuntu4.2+esm3"
          }
        ],
        "priority_reason": "OpenSSL developers have rated this low severity"
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:16.04:LTS",
        "name": "nodejs",
        "purl": "pkg:deb/ubuntu/nodejs@4.2.6~dfsg-1ubuntu4.2+esm3?arch=source\u0026distro=esm-apps/xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.10.25~dfsg2-2ubuntu1",
        "4.2.2~dfsg-1",
        "4.2.3~dfsg-1",
        "4.2.4~dfsg-1ubuntu1",
        "4.2.4~dfsg-2",
        "4.2.6~dfsg-1ubuntu1",
        "4.2.6~dfsg-1ubuntu4",
        "4.2.6~dfsg-1ubuntu4.1",
        "4.2.6~dfsg-1ubuntu4.2",
        "4.2.6~dfsg-1ubuntu4.2+esm1",
        "4.2.6~dfsg-1ubuntu4.2+esm2",
        "4.2.6~dfsg-1ubuntu4.2+esm3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "nodejs",
            "binary_version": "8.10.0~dfsg-2ubuntu0.4+esm6"
          }
        ],
        "priority_reason": "OpenSSL developers have rated this low severity"
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:18.04:LTS",
        "name": "nodejs",
        "purl": "pkg:deb/ubuntu/nodejs@8.10.0~dfsg-2ubuntu0.4+esm6?arch=source\u0026distro=esm-apps/bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "6.11.4~dfsg-1ubuntu1",
        "6.11.4~dfsg-1ubuntu2",
        "6.12.0~dfsg-1ubuntu1",
        "6.12.0~dfsg-2ubuntu1",
        "6.12.0~dfsg-2ubuntu2",
        "8.10.0~dfsg-2",
        "8.10.0~dfsg-2ubuntu0.2",
        "8.10.0~dfsg-2ubuntu0.3",
        "8.10.0~dfsg-2ubuntu0.4",
        "8.10.0~dfsg-2ubuntu0.4+esm1",
        "8.10.0~dfsg-2ubuntu0.4+esm2",
        "8.10.0~dfsg-2ubuntu0.4+esm3",
        "8.10.0~dfsg-2ubuntu0.4+esm4",
        "8.10.0~dfsg-2ubuntu0.4+esm5",
        "8.10.0~dfsg-2ubuntu0.4+esm6"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "efi-shell-aa64",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "efi-shell-loongarch64",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "efi-shell-riscv64",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "efi-shell-x64",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "ovmf",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "ovmf-amdsev",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "ovmf-generic",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "ovmf-inteltdx",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "ovmf-legacy",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "qemu-efi-aarch64",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "qemu-efi-loongarch64",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "qemu-efi-riscv64",
            "binary_version": "2025.11-3ubuntu7.2"
          }
        ],
        "priority_reason": "OpenSSL developers have rated this low severity"
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "edk2",
        "purl": "pkg:deb/ubuntu/edk2@2025.11-3ubuntu7.2?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2025.02-8ubuntu3",
        "2025.11-3ubuntu6",
        "2025.11-3ubuntu7",
        "2025.11-3ubuntu7.2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "efi-shell-aa64-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "efi-shell-loongarch64-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "efi-shell-riscv64-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "efi-shell-x64-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "ovmf-amdsev-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "ovmf-generic-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "ovmf-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "ovmf-inteltdx-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "ovmf-legacy-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "qemu-efi-aarch64-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "qemu-efi-loongarch64-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "qemu-efi-riscv64-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          }
        ],
        "priority_reason": "OpenSSL developers have rated this low severity"
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "edk2-hwe",
        "purl": "pkg:deb/ubuntu/edk2-hwe@2025.11-3ubuntu8.2?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2025.11-3ubuntu6",
        "2025.11-3ubuntu8",
        "2025.11-3ubuntu8.2"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libssl3t64",
            "binary_version": "3.5.5-1ubuntu3.4"
          },
          {
            "binary_name": "openssl",
            "binary_version": "3.5.5-1ubuntu3.4"
          },
          {
            "binary_name": "openssl-provider-legacy",
            "binary_version": "3.5.5-1ubuntu3.4"
          }
        ],
        "priority_reason": "OpenSSL developers have rated this low severity"
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "openssl",
        "purl": "pkg:deb/ubuntu/openssl@3.5.5-1ubuntu3.4?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.5.5-1ubuntu3.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.5.3-1ubuntu2",
        "3.5.5-1ubuntu1",
        "3.5.5-1ubuntu3",
        "3.5.5-1ubuntu3.2",
        "3.5.5-1ubuntu3.3"
      ]
    }
  ],
  "aliases": [],
  "details": "Issue summary: When OpenSSL processes QUIC traffic from a peer that repeatedly sends ack-eliciting packets while not acknowledging ACK-only responses, the QUIC stack can retain ACK-only packet metadata for the lifetime of the connection. Impact summary: A remote peer that can complete a QUIC handshake can cause connection-scoped memory growth which may lead to Denial of Service through memory exhaustion, especially with sustained traffic or many concurrent QUIC connections. CWE: CWE-770: Allocation of Resources Without Limits or Throttling Description: When the OpenSSL QUIC stack sends an ACK-only packet, there is no requirement by the QUIC protocol that the peer will acknowledge that ACK-only packet (i.e. it is itself not ack-eliciting). However, the OpenSSL implementation stores the metadata about the ACK frames regardless. In and of itself that\u0027s ok, but if a malicious peer establishes a connection, and then drives the connection such that ACK-only packets are forced from the OpenSSL implementation peer (i.e., by sending numerous PING frames), and then withholding any subsequent acks for ack-eliciting data, like legitimate data, said malicious peer can force inappropriate memory growth on the OpenSSL peer, potentially leading to a Denial of Service. The fix is to ensure that we account for the transmission of the ACK-only packet in the packet histories high and low watermark without actually storing the ACK-only packet metadata itself. FIPS impact: no The OpenSSL FIPS module is not affected as the QUIC code is outside the FIPS module boundary.",
  "id": "UBUNTU-CVE-2026-63075",
  "modified": "2026-09-16T11:36:44Z",
  "published": "2026-08-25T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-63075"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-63075"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8678-1"
    }
  ],
  "related": [
    "USN-8678-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "low",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-63075"
  ]
}



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