CVE-2026-27857CWE-400

Sending "NOOP (((...)))" command with 4000 parenthesis open+close results in ~1MB extra memory usage

Medium · published March 27, 2026

CVSS v3.1
4.3
EPSS
1%
Percentile
56.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
4.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
CVSS v4.0
Not supplied
EPSS
0.00804 · 56.3th percentile
Weakness
CWE-400 · Uncontrolled Resource Consumption
Published
2026-03-27T08:10Z
EPSS history
Timeline
  • 27 MAR 08:10Z
    Sending "NOOP (((...)))" command with 4000 parenthesis open+close results in ~1MB extra memory usage
    cvelistv5