usn-8678-3
Vulnerability from osv_ubuntu
USN-8673-1 fixed vulnerabilities in OpenSSL. The update inadvertently left out the fix for CVE-2026-75803 in Ubuntu 26.04 LTS. This update fixes the problem.
We apologize for the inconvenience.
Original advisory details:
It was discovered that OpenSSL incorrectly handled the QUIC server incoming channel queue. A remote attacker could possibly use this issue to cause OpenSSL to use excessive resources, leading to a denial of service. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-14456)
It was discovered that OpenSSL incorrectly handled signature algorithm selection when using Raw Public Keys. A remote attacker could possibly use this issue to cause OpenSSL to crash, resulting in a denial of service. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-14457)
It was discovered that OpenSSL incorrectly handled QUIC INITIAL packet processing. A remote attacker could possibly use this issue to cause OpenSSL to crash, resulting in a denial of service. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-18798)
It was discovered that OpenSSL incorrectly handled buffering of DTLS records for a future epoch. A remote attacker could possibly use this issue to cause OpenSSL to use excessive resources, leading to a denial of service. (CVE-2026-54874)
It was discovered that OpenSSL incorrectly handled CMS key unwrapping. A remote attacker could possibly use this issue to cause a heap buffer overflow, leading to a denial of service or arbitrary code execution. (CVE-2026-63072)
It was discovered that OpenSSL incorrectly validated the sender distinguished name in CMP response messages. A remote attacker could possibly use this issue to cause OpenSSL to crash, resulting in a denial of service. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-63073)
It was discovered that OpenSSL incorrectly limited the growth of an internal certificate cache used during CMP operations. A remote attacker could possibly use this issue to cause OpenSSL to use excessive resources, leading to a denial of service. (CVE-2026-63074)
It was discovered that OpenSSL incorrectly handled QUIC ACK-only packet retention. A remote attacker could possibly use this issue to cause OpenSSL to use excessive resources, leading to a denial of service. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-63075)
It was discovered that OpenSSL incorrectly handled CMP protection algorithm validation. A remote attacker could possibly use this issue to cause OpenSSL to crash, resulting in a denial of service. (CVE-2026-63076)
It was discovered that OpenSSL incorrectly verified authentication tags when using certain AEAD ciphers via the EVP_Cipher() interface. An attacker could possibly use this issue to perform AEAD forgery attacks. (CVE-2026-75803)
| URL | Type | |
|---|---|---|
{
"affected": [
{
"database_specific": {
"cves_map": {
"cves": [
{
"id": "CVE-2026-75803",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
"type": "CVSS_V3"
},
{
"score": "low",
"type": "Ubuntu"
}
]
}
],
"ecosystem": "Ubuntu:26.04:LTS"
}
},
"ecosystem_specific": {
"availability": "No subscription required",
"binaries": [
{
"binary_name": "libssl3t64",
"binary_version": "3.5.5-1ubuntu3.5"
},
{
"binary_name": "openssl",
"binary_version": "3.5.5-1ubuntu3.5"
},
{
"binary_name": "openssl-provider-legacy",
"binary_version": "3.5.5-1ubuntu3.5"
}
]
},
"package": {
"ecosystem": "Ubuntu:26.04:LTS",
"name": "openssl",
"purl": "pkg:deb/ubuntu/openssl@3.5.5-1ubuntu3.5?arch=source\u0026distro=resolute"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "3.5.5-1ubuntu3.5"
}
],
"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"
]
}
],
"aliases": [],
"details": "USN-8673-1 fixed vulnerabilities in OpenSSL. The update inadvertently left\nout the fix for CVE-2026-75803 in Ubuntu 26.04 LTS. This update fixes the\nproblem.\n\nWe apologize for the inconvenience.\n\nOriginal advisory details:\n\n It was discovered that OpenSSL incorrectly handled the QUIC server incoming\n channel queue. A remote attacker could possibly use this issue to cause\n OpenSSL to use excessive resources, leading to a denial of service. This\n issue only affected Ubuntu 26.04 LTS. (CVE-2026-14456)\n\n It was discovered that OpenSSL incorrectly handled signature algorithm\n selection when using Raw Public Keys. A remote attacker could possibly use\n this issue to cause OpenSSL to crash, resulting in a denial of service.\n This issue only affected Ubuntu 26.04 LTS. (CVE-2026-14457)\n\n It was discovered that OpenSSL incorrectly handled QUIC INITIAL packet\n processing. A remote attacker could possibly use this issue to cause\n OpenSSL to crash, resulting in a denial of service. This issue only\n affected Ubuntu 26.04 LTS. (CVE-2026-18798)\n\n It was discovered that OpenSSL incorrectly handled buffering of DTLS\n records for a future epoch. A remote attacker could possibly use this issue\n to cause OpenSSL to use excessive resources, leading to a denial of\n service. (CVE-2026-54874)\n\n It was discovered that OpenSSL incorrectly handled CMS key unwrapping. A\n remote attacker could possibly use this issue to cause a heap buffer\n overflow, leading to a denial of service or arbitrary code execution.\n (CVE-2026-63072)\n\n It was discovered that OpenSSL incorrectly validated the sender\n distinguished name in CMP response messages. A remote attacker could\n possibly use this issue to cause OpenSSL to crash, resulting in a denial of\n service. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-63073)\n\n It was discovered that OpenSSL incorrectly limited the growth of an\n internal certificate cache used during CMP operations. A remote attacker\n could possibly use this issue to cause OpenSSL to use excessive resources,\n leading to a denial of service. (CVE-2026-63074)\n\n It was discovered that OpenSSL incorrectly handled QUIC ACK-only packet\n retention. A remote attacker could possibly use this issue to cause OpenSSL\n to use excessive resources, leading to a denial of service. This issue only\n affected Ubuntu 26.04 LTS. (CVE-2026-63075)\n\n It was discovered that OpenSSL incorrectly handled CMP protection algorithm\n validation. A remote attacker could possibly use this issue to cause\n OpenSSL to crash, resulting in a denial of service. (CVE-2026-63076)\n\n It was discovered that OpenSSL incorrectly verified authentication tags\n when using certain AEAD ciphers via the EVP_Cipher() interface. An attacker\n could possibly use this issue to perform AEAD forgery attacks.\n (CVE-2026-75803)",
"id": "USN-8678-3",
"modified": "2026-09-03T12:42:24Z",
"published": "2026-08-31T12:18:40Z",
"references": [
{
"type": "ADVISORY",
"url": "https://ubuntu.com/security/notices/USN-8678-3"
},
{
"type": "REPORT",
"url": "https://ubuntu.com/security/CVE-2026-75803"
}
],
"related": [],
"schema_version": "1.7.0",
"summary": "openssl vulnerability",
"upstream": [
"UBUNTU-CVE-2026-75803"
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.