CVE-2026-27857
Full vulnerability record from the local CVENow database.
Description
Sending "NOOP (((...)))" command with 4000 parenthesis open+close results in ~1MB extra memory usage. Longer commands will result in client disconnection. This 1 MB can be left allocated for longer time periods by not sending the command ending LF. So attacker could connect possibly from even a single IP and create 1000 connections to allocate 1 GB of memory, which would likely result in reaching VSZ limit and killing the process and its other proxied connections. Attacker could connect possibly from even a single IP and create 1000 connections to allocate 1 GB of memory, which would likely result in reaching VSZ limit and killing the process and its other proxied connections. Install fixed version, there is no other remediation. No publicly available exploits are known.
Severity
HIGH
CVSS score
7.5
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2026-03-27 09:16:19.917000
Last modified
2026-10-26 22:10:00.163000
View original CVE JSON
{
"id": "CVE-2026-27857",
"sourceIdentifier": "[email protected]",
"published": "2026-03-27T09:16:19.917",
"lastModified": "2026-10-26T22:10:00.163",
"vulnStatus": "Modified",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "Sending \"NOOP (((...)))\" command with 4000 parenthesis open+close results in ~1MB extra memory usage. Longer commands will result in client disconnection. This 1 MB can be left allocated for longer time periods by not sending the command ending LF. So attacker could connect possibly from even a single IP and create 1000 connections to allocate 1 GB of memory, which would likely result in reaching VSZ limit and killing the process and its other proxied connections. Attacker could connect possibly from even a single IP and create 1000 connections to allocate 1 GB of memory, which would likely result in reaching VSZ limit and killing the process and its other proxied connections. Install fixed version, there is no other remediation. No publicly available exploits are known."
},
{
"lang": "es",
"value": "El envío del comando ’NOOP (((...)))’ con 4000 paréntesis abiertos+cerrados resulta en un uso de memoria adicional de ~1MB. Comandos más largos resultarán en la desconexión del cliente. Este 1 MB puede dejarse asignado por períodos de tiempo más prolongados al no enviar el LF de terminación del comando. Así, un atacante podría conectarse posiblemente incluso desde una única IP y crear 1000 conexiones para asignar 1 GB de memoria, lo que probablemente resultaría en alcanzar el límite de VSZ y matar el proceso y sus otras conexiones proxy. Un atacante podría conectarse posiblemente incluso desde una única IP y crear 1000 conexiones para asignar 1 GB de memoria, lo que probablemente resultaría en alcanzar el límite de VSZ y matar el proceso y sus otras conexiones proxy. Instale la versión corregida, no hay otra remediación. No se conocen exploits disponibles públicamente."
}
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