UBUNTU-CVE-2026-42772 (CVE-2026-42772)
Vulnerability from osv_ubuntu – Published: 2026-09-29 16:17 – Updated: 2026-10-17 09:40 – Source websiteIssue summary: The QUIC stream reassembly algorithm performance deteriorates progressively as packets are arriving out of order. The worst case has a quadratic complexity proportional to the number of stream frames kept in the buffer for the received stream data. Impact summary: A remote QUIC peer that completes the handshake can create a connection-scoped CPU pressure and potentially a Denial of Service using compliant STREAM frames inside the advertised receive window, with low attacker bandwidth. CWE: CWE-407: Inefficient Algorithmic Complexity Description: OpenSSL manages received QUIC stream fragments using a doubly-linked list. While it optimizes for append operations (at the end of the list), it falls back to a head-to-tail linear search for any fragment that does not immediately follow the current tail. By manipulating the sequence of offsets, an attacker can force the server to perform O(n^2) operations, consuming excessive CPU time for the QUIC process. FIPS impact: no The FIPS module is not affected as the QUIC implementation is outside of the OpenSSL FIPS module boundary.
{
"affected": [
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "libnode72",
"binary_version": "12.22.9~dfsg-1ubuntu3.6+esm2"
},
{
"binary_name": "nodejs",
"binary_version": "12.22.9~dfsg-1ubuntu3.6+esm2"
}
],
"priority_reason": "OpenSSL developers have rated this issue as being low severity"
},
"package": {
"ecosystem": "Ubuntu:Pro:22.04:LTS",
"name": "nodejs",
"purl": "pkg:deb/ubuntu/nodejs@12.22.9~dfsg-1ubuntu3.6+esm2?arch=source\u0026distro=esm-apps/jammy"
},
"ranges": [
{
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{
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}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"12.22.5~dfsg-5ubuntu1",
"12.22.7~dfsg-2ubuntu1",
"12.22.7~dfsg-2ubuntu3",
"12.22.9~dfsg-1ubuntu2",
"12.22.9~dfsg-1ubuntu3",
"12.22.9~dfsg-1ubuntu3.1",
"12.22.9~dfsg-1ubuntu3.2",
"12.22.9~dfsg-1ubuntu3.3",
"12.22.9~dfsg-1ubuntu3.4",
"12.22.9~dfsg-1ubuntu3.5",
"12.22.9~dfsg-1ubuntu3.6",
"12.22.9~dfsg-1ubuntu3.6+esm2"
]
},
{
"ecosystem_specific": {
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{
"binary_name": "efi-shell-aa64",
"binary_version": "2026.05-2ubuntu3"
},
{
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"binary_version": "2026.05-2ubuntu3"
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{
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"binary_version": "2026.05-2ubuntu3"
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{
"binary_name": "efi-shell-x64",
"binary_version": "2026.05-2ubuntu3"
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{
"binary_name": "ovmf",
"binary_version": "2026.05-2ubuntu3"
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{
"binary_name": "ovmf-amdsev",
"binary_version": "2026.05-2ubuntu3"
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{
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{
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"binary_name": "qemu-efi-loongarch64",
"binary_version": "2026.05-2ubuntu3"
},
{
"binary_name": "qemu-efi-riscv64",
"binary_version": "2026.05-2ubuntu3"
}
],
"priority_reason": "OpenSSL developers have rated this issue as being low severity"
},
"package": {
"ecosystem": "Ubuntu:26.10",
"name": "edk2",
"purl": "pkg:deb/ubuntu/edk2@2026.05-2ubuntu3?arch=source\u0026distro=stonking"
},
"ranges": [
{
"events": [
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"versions": [
"2025.11-3ubuntu7",
"2025.11-3ubuntu8",
"2026.05-2ubuntu1",
"2026.05-2ubuntu2",
"2026.05-2ubuntu3"
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},
{
"ecosystem_specific": {
"binaries": [
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"binary_name": "efi-shell-aa64-hwe",
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{
"binary_name": "efi-shell-loongarch64-hwe",
"binary_version": "2026.05-2ubuntu3"
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{
"binary_name": "efi-shell-riscv64-hwe",
"binary_version": "2026.05-2ubuntu3"
},
{
"binary_name": "efi-shell-x64-hwe",
"binary_version": "2026.05-2ubuntu3"
},
{
"binary_name": "ovmf-amdsev-hwe",
"binary_version": "2026.05-2ubuntu3"
},
{
"binary_name": "ovmf-generic-hwe",
"binary_version": "2026.05-2ubuntu3"
},
{
"binary_name": "ovmf-hwe",
"binary_version": "2026.05-2ubuntu3"
},
{
"binary_name": "ovmf-inteltdx-hwe",
"binary_version": "2026.05-2ubuntu3"
},
{
"binary_name": "ovmf-legacy-hwe",
"binary_version": "2026.05-2ubuntu3"
},
{
"binary_name": "qemu-efi-aarch64-hwe",
"binary_version": "2026.05-2ubuntu3"
},
{
"binary_name": "qemu-efi-loongarch64-hwe",
"binary_version": "2026.05-2ubuntu3"
},
{
"binary_name": "qemu-efi-riscv64-hwe",
"binary_version": "2026.05-2ubuntu3"
}
],
"priority_reason": "OpenSSL developers have rated this issue as being low severity"
},
"package": {
"ecosystem": "Ubuntu:26.10",
"name": "edk2-hwe",
"purl": "pkg:deb/ubuntu/edk2-hwe@2026.05-2ubuntu3?arch=source\u0026distro=stonking"
},
"ranges": [
{
"events": [
{
"introduced": "0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2025.11-3ubuntu8",
"2025.11-3ubuntu9",
"2026.05-2ubuntu1",
"2026.05-2ubuntu2",
"2026.05-2ubuntu3"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "efi-shell-aa64",
"binary_version": "2025.11-3ubuntu7.3"
},
{
"binary_name": "efi-shell-loongarch64",
"binary_version": "2025.11-3ubuntu7.3"
},
{
"binary_name": "efi-shell-riscv64",
"binary_version": "2025.11-3ubuntu7.3"
},
{
"binary_name": "efi-shell-x64",
"binary_version": "2025.11-3ubuntu7.3"
},
{
"binary_name": "ovmf",
"binary_version": "2025.11-3ubuntu7.3"
},
{
"binary_name": "ovmf-amdsev",
"binary_version": "2025.11-3ubuntu7.3"
},
{
"binary_name": "ovmf-generic",
"binary_version": "2025.11-3ubuntu7.3"
},
{
"binary_name": "ovmf-inteltdx",
"binary_version": "2025.11-3ubuntu7.3"
},
{
"binary_name": "ovmf-legacy",
"binary_version": "2025.11-3ubuntu7.3"
},
{
"binary_name": "qemu-efi-aarch64",
"binary_version": "2025.11-3ubuntu7.3"
},
{
"binary_name": "qemu-efi-loongarch64",
"binary_version": "2025.11-3ubuntu7.3"
},
{
"binary_name": "qemu-efi-riscv64",
"binary_version": "2025.11-3ubuntu7.3"
}
],
"priority_reason": "OpenSSL developers have rated this issue as being low severity"
},
"package": {
"ecosystem": "Ubuntu:26.04:LTS",
"name": "edk2",
"purl": "pkg:deb/ubuntu/edk2@2025.11-3ubuntu7.3?arch=source\u0026distro=resolute"
},
"ranges": [
{
"events": [
{
"introduced": "0"
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"versions": [
"2025.02-8ubuntu3",
"2025.11-3ubuntu6",
"2025.11-3ubuntu7",
"2025.11-3ubuntu7.2",
"2025.11-3ubuntu7.3"
]
},
{
"ecosystem_specific": {
"binaries": [
{
"binary_name": "efi-shell-aa64-hwe",
"binary_version": "2025.11-3ubuntu8.2"
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{
"binary_name": "efi-shell-loongarch64-hwe",
"binary_version": "2025.11-3ubuntu8.2"
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{
"binary_name": "efi-shell-riscv64-hwe",
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"binary_version": "2025.11-3ubuntu8.2"
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"binary_name": "ovmf-amdsev-hwe",
"binary_version": "2025.11-3ubuntu8.2"
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{
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{
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"binary_version": "2025.11-3ubuntu8.2"
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{
"binary_name": "qemu-efi-riscv64-hwe",
"binary_version": "2025.11-3ubuntu8.2"
}
],
"priority_reason": "OpenSSL developers have rated this issue as being 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": [
{
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"versions": [
"2025.11-3ubuntu6",
"2025.11-3ubuntu8",
"2025.11-3ubuntu8.2"
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},
{
"ecosystem_specific": {
"availability": "No subscription required",
"binaries": [
{
"binary_name": "libssl3t64",
"binary_version": "3.5.5-1ubuntu3.7"
},
{
"binary_name": "openssl",
"binary_version": "3.5.5-1ubuntu3.7"
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{
"binary_name": "openssl-provider-legacy",
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"priority_reason": "OpenSSL developers have rated this issue as being low severity"
},
"package": {
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"name": "openssl",
"purl": "pkg:deb/ubuntu/openssl@3.5.5-1ubuntu3.7?arch=source\u0026distro=resolute"
},
"ranges": [
{
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{
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"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",
"3.5.5-1ubuntu3.4",
"3.5.5-1ubuntu3.5",
"3.5.5-1ubuntu3.6"
]
}
],
"aliases": [],
"details": "Issue summary: The QUIC stream reassembly algorithm performance deteriorates progressively as packets are arriving out of order. The worst case has a quadratic complexity proportional to the number of stream frames kept in the buffer for the received stream data. Impact summary: A remote QUIC peer that completes the handshake can create a connection-scoped CPU pressure and potentially a Denial of Service using compliant STREAM frames inside the advertised receive window, with low attacker bandwidth. CWE: CWE-407: Inefficient Algorithmic Complexity Description: OpenSSL manages received QUIC stream fragments using a doubly-linked list. While it optimizes for append operations (at the end of the list), it falls back to a head-to-tail linear search for any fragment that does not immediately follow the current `tail`. By manipulating the sequence of offsets, an attacker can force the server to perform O(n^2) operations, consuming excessive CPU time for the QUIC process. FIPS impact: no The FIPS module is not affected as the QUIC implementation is outside of the OpenSSL FIPS module boundary.",
"id": "UBUNTU-CVE-2026-42772",
"modified": "2026-10-17T09:40:59Z",
"published": "2026-09-29T16:17:00Z",
"references": [
{
"type": "REPORT",
"url": "https://ubuntu.com/security/CVE-2026-42772"
},
{
"type": "REPORT",
"url": "https://www.cve.org/CVERecord?id=CVE-2026-42772"
},
{
"type": "REPORT",
"url": "https://openssl-library.org/news/secadv/20260929.txt"
},
{
"type": "ADVISORY",
"url": "https://ubuntu.com/security/notices/USN-8861-1"
}
],
"related": [
"USN-8861-1"
],
"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:L",
"type": "CVSS_V3"
},
{
"score": "low",
"type": "Ubuntu"
}
],
"upstream": [
"CVE-2026-42772"
]
}
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| Author | Source | Type | Date | Other |
|---|
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