OESA-2026-2943 (CVE-2026-56123)
Vulnerability from osv_openeuler – Published: 2026-07-09 11:11 – Updated: 2026-08-06 11:11 – Source websiteSocat is a relay for bidirectional data transfer between two independent data channels. Each of these data channels may be a file, pipe, device (serial line etc. or a pseudo terminal), a socket (UNIX, IP4, IP6 - raw, UDP, TCP), an SSL socket, proxy CONNECT connection, a file descriptor (stdin etc.), the GNU line editor (readline), a program, or a combination of two of these.
Security Fix(es):
socat versions 1.8.0.0 through 1.8.1.1 contain a heap-based buffer overflow vulnerability that allows a malicious SOCKS5 proxy server to overwrite adjacent heap memory by exploiting a sign-extension flaw in the DOMAINNAME reply parser. During connection setup, the domain name length byte is read through a signed char field causing a negative bytes_to_read value that is implicitly converted to size_t, resulting in an unbounded heap write into the 262-byte reply buffer with attacker-controlled size and content.(CVE-2026-56123)
| URL | Type | |
|---|---|---|
{
"affected": [
{
"ecosystem_specific": {
"aarch64": [
"socat-1.8.1.3-1.oe2403sp1.aarch64.rpm",
"socat-debuginfo-1.8.1.3-1.oe2403sp1.aarch64.rpm",
"socat-debugsource-1.8.1.3-1.oe2403sp1.aarch64.rpm"
],
"noarch": [
"socat-help-1.8.1.3-1.oe2403sp1.noarch.rpm"
],
"src": [
"socat-1.8.1.3-1.oe2403sp1.src.rpm"
],
"x86_64": [
"socat-1.8.1.3-1.oe2403sp1.x86_64.rpm",
"socat-debuginfo-1.8.1.3-1.oe2403sp1.x86_64.rpm",
"socat-debugsource-1.8.1.3-1.oe2403sp1.x86_64.rpm"
]
},
"package": {
"ecosystem": "openEuler:24.03-LTS-SP1",
"name": "socat",
"purl": "pkg:rpm/openEuler/socat\u0026distro=openEuler-24.03-LTS-SP1"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.8.1.3-1.oe2403sp1"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"database_specific": {
"severity": "Critical"
},
"details": "Socat is a relay for bidirectional data transfer between two independent data channels. Each of these data channels may be a file, pipe, device (serial line etc. or a pseudo terminal), a socket (UNIX, IP4, IP6 - raw, UDP, TCP), an SSL socket, proxy CONNECT connection, a file descriptor (stdin etc.), the GNU line editor (readline), a program, or a combination of two of these.\r\n\r\nSecurity Fix(es):\n\nsocat versions 1.8.0.0 through 1.8.1.1 contain a heap-based buffer overflow vulnerability that allows a malicious SOCKS5 proxy server to overwrite adjacent heap memory by exploiting a sign-extension flaw in the DOMAINNAME reply parser. During connection setup, the domain name length byte is read through a signed char field causing a negative bytes_to_read value that is implicitly converted to size_t, resulting in an unbounded heap write into the 262-byte reply buffer with attacker-controlled size and content.(CVE-2026-56123)",
"id": "OESA-2026-2943",
"modified": "2026-08-06T11:11:51Z",
"published": "2026-07-09T11:11:51Z",
"references": [
{
"type": "ADVISORY",
"url": "https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-2943"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-56123"
}
],
"schema_version": "1.7.2",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
],
"summary": "socat security update",
"upstream": [
"CVE-2026-56123"
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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- 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.
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