---
id: "CVE-2014-0196"
kind: "vulnerability"
aliases: ["CVE-2014-0196"]
title: "The n_tty_write function in drivers/tty/n_tty.c in the Linux kernel through 3.14.3 does not properly manage tty\u2026"
severity: "high"
cvss: 6.9
epss: null
exploited: true
status: "open"
category: "infrastructure"
products: [{"name": "linux kernel", "fixed": ["3.2.59"], "affected": "> 2.6.31, < 3.2.59", "ecosystem": "vendor"}, {"name": "linux kernel", "fixed": ["3.4.91"], "affected": ">= 3.3, < 3.4.91", "ecosystem": "vendor"}, {"name": "linux kernel", "fixed": ["3.10.40"], "affected": ">= 3.5, < 3.10.40", "ecosystem": "vendor"}, {"name": "linux kernel", "fixed": ["3.12.20"], "affected": ">= 3.11, < 3.12.20", "ecosystem": "vendor"}, {"name": "linux kernel", "fixed": ["3.14.4"], "affected": ">= 3.13, < 3.14.4", "ecosystem": "vendor"}, {"name": "linux kernel", "fixed": [], "affected": "= 2.6.31", "ecosystem": "vendor"}, {"name": "debian linux", "fixed": [], "affected": "= 6.0", "ecosystem": "vendor"}, {"name": "debian linux", "fixed": [], "affected": "= 7.0", "ecosystem": "vendor"}, {"name": "redhat enterprise linux", "fixed": [], "affected": "= 6.0", "ecosystem": "vendor"}, {"name": "redhat enterprise linux eus", "fixed": [], "affected": "= 6.3", "ecosystem": "vendor"}, {"name": "redhat enterprise linux eus", "fixed": [], "affected": "= 6.4", "ecosystem": "vendor"}, {"name": "redhat enterprise linux server eus", "fixed": [], "affected": "= 6.3", "ecosystem": "vendor"}, {"name": "suse linux enterprise desktop", "fixed": [], "affected": "= 11", "ecosystem": "vendor"}, {"name": "suse linux enterprise high availability extension", "fixed": [], "affected": "= 11", "ecosystem": "vendor"}, {"name": "suse linux enterprise server", "fixed": [], "affected": "= 11", "ecosystem": "vendor"}, {"name": "oracle linux", "fixed": [], "affected": "= 6", "ecosystem": "vendor"}, {"name": "canonical ubuntu linux", "fixed": [], "affected": "= 10.04", "ecosystem": "vendor"}, {"name": "canonical ubuntu linux", "fixed": [], "affected": "= 12.04", "ecosystem": "vendor"}, {"name": "canonical ubuntu linux", "fixed": [], "affected": "= 12.10", "ecosystem": "vendor"}, {"name": "canonical ubuntu linux", "fixed": [], "affected": "= 13.10", "ecosystem": "vendor"}, {"name": "canonical ubuntu linux", "fixed": [], "affected": "= 14.04", "ecosystem": "vendor"}, {"name": "f5 big-ip access policy manager", "fixed": [], "affected": ">= 11.1.0, <= 11.5.1", "ecosystem": "vendor"}, {"name": "f5 big-ip advanced firewall manager", "fixed": [], "affected": ">= 11.3.0, <= 11.5.1", "ecosystem": "vendor"}, {"name": "f5 big-ip analytics", "fixed": [], "affected": ">= 11.1.0, <= 11.5.1", "ecosystem": "vendor"}, {"name": "f5 big-ip application acceleration manager", "fixed": [], "affected": ">= 11.4.0, <= 11.5.1", "ecosystem": "vendor"}, {"name": "f5 big-ip application security manager", "fixed": [], "affected": ">= 11.1.0, <= 11.5.1", "ecosystem": "vendor"}, {"name": "f5 big-ip edge gateway", "fixed": [], "affected": ">= 11.1.0, <= 11.3.0", "ecosystem": "vendor"}, {"name": "f5 big-ip global traffic manager", "fixed": [], "affected": ">= 11.1.0, <= 11.5.1", "ecosystem": "vendor"}, {"name": "f5 big-ip link controller", "fixed": [], "affected": ">= 11.1.0, <= 11.5.1", "ecosystem": "vendor"}, {"name": "f5 big-ip local traffic manager", "fixed": [], "affected": ">= 11.1.0, <= 11.5.1", "ecosystem": "vendor"}, {"name": "f5 big-ip policy enforcement manager", "fixed": [], "affected": ">= 11.3.0, <= 11.5.1", "ecosystem": "vendor"}, {"name": "f5 big-ip protocol security module", "fixed": [], "affected": ">= 11.1.0, <= 11.4.1", "ecosystem": "vendor"}, {"name": "f5 big-ip wan optimization manager", "fixed": [], "affected": ">= 11.1.0, <= 11.3.0", "ecosystem": "vendor"}, {"name": "f5 big-ip webaccelerator", "fixed": [], "affected": ">= 11.1.0, <= 11.3.0", "ecosystem": "vendor"}, {"name": "f5 big-iq application delivery controller", "fixed": [], "affected": "= 4.5.0", "ecosystem": "vendor"}, {"name": "f5 big-iq centralized management", "fixed": [], "affected": "= 4.6.0", "ecosystem": "vendor"}, {"name": "f5 big-iq cloud", "fixed": [], "affected": ">= 4.0.0, <= 4.5.0", "ecosystem": "vendor"}, {"name": "f5 big-iq cloud and orchestration", "fixed": [], "affected": "= 1.0.0", "ecosystem": "vendor"}, {"name": "f5 big-iq device", "fixed": [], "affected": ">= 4.2.0, <= 4.5.0", "ecosystem": "vendor"}, {"name": "f5 big-iq security", "fixed": [], "affected": ">= 4.0.0, <= 4.5.0", "ecosystem": "vendor"}, {"name": "Linux Kernel", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["exploited", "infrastructure", "linux", "self-hosted", "shared-hosts"]
not_affected_if: ["no-local-untrusted-users", "unpatched-kernel-not-used"]
published_at: "2014-05-07T10:55:04+00:00"
first_seen_at: "2026-10-23T19:11:52+00:00"
updated_at: "2026-10-24T00:09:51+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2014-0196", "first_seen_at": "2026-10-23T19:11:52+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2014-0196", "first_seen_at": "2026-10-23T22:29:04+00:00"}]
---

# The n_tty_write function in drivers/tty/n_tty.c in the Linux kernel through 3.14.3 does not properly manage tty…

A race condition in the Linux kernel n_tty_write function lets a local user crash the system or gain root privileges using long read and write operations. CISA lists it as actively exploited in the wild.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:linux kernel affected > 2.6.31, < 3.2.59 fixed 3.2.59
- vendor:linux kernel affected >= 3.3, < 3.4.91 fixed 3.4.91
- vendor:linux kernel affected >= 3.5, < 3.10.40 fixed 3.10.40
- vendor:linux kernel affected >= 3.11, < 3.12.20 fixed 3.12.20
- vendor:linux kernel affected >= 3.13, < 3.14.4 fixed 3.14.4
- vendor:linux kernel affected = 2.6.31 fixed ?
- vendor:debian linux affected = 6.0 fixed ?
- vendor:debian linux affected = 7.0 fixed ?
- vendor:redhat enterprise linux affected = 6.0 fixed ?
- vendor:redhat enterprise linux eus affected = 6.3 fixed ?
- vendor:redhat enterprise linux eus affected = 6.4 fixed ?
- vendor:redhat enterprise linux server eus affected = 6.3 fixed ?
- vendor:suse linux enterprise desktop affected = 11 fixed ?
- vendor:suse linux enterprise high availability extension affected = 11 fixed ?
- vendor:suse linux enterprise server affected = 11 fixed ?
- vendor:oracle linux affected = 6 fixed ?
- vendor:canonical ubuntu linux affected = 10.04 fixed ?
- vendor:canonical ubuntu linux affected = 12.04 fixed ?
- vendor:canonical ubuntu linux affected = 12.10 fixed ?
- vendor:canonical ubuntu linux affected = 13.10 fixed ?
- vendor:canonical ubuntu linux affected = 14.04 fixed ?
- vendor:f5 big-ip access policy manager affected >= 11.1.0, <= 11.5.1 fixed ?
- vendor:f5 big-ip advanced firewall manager affected >= 11.3.0, <= 11.5.1 fixed ?
- vendor:f5 big-ip analytics affected >= 11.1.0, <= 11.5.1 fixed ?
- vendor:f5 big-ip application acceleration manager affected >= 11.4.0, <= 11.5.1 fixed ?
- vendor:f5 big-ip application security manager affected >= 11.1.0, <= 11.5.1 fixed ?
- vendor:f5 big-ip edge gateway affected >= 11.1.0, <= 11.3.0 fixed ?
- vendor:f5 big-ip global traffic manager affected >= 11.1.0, <= 11.5.1 fixed ?
- vendor:f5 big-ip link controller affected >= 11.1.0, <= 11.5.1 fixed ?
- vendor:f5 big-ip local traffic manager affected >= 11.1.0, <= 11.5.1 fixed ?
- vendor:f5 big-ip policy enforcement manager affected >= 11.3.0, <= 11.5.1 fixed ?
- vendor:f5 big-ip protocol security module affected >= 11.1.0, <= 11.4.1 fixed ?
- vendor:f5 big-ip wan optimization manager affected >= 11.1.0, <= 11.3.0 fixed ?
- vendor:f5 big-ip webaccelerator affected >= 11.1.0, <= 11.3.0 fixed ?
- vendor:f5 big-iq application delivery controller affected = 4.5.0 fixed ?
- vendor:f5 big-iq centralized management affected = 4.6.0 fixed ?
- vendor:f5 big-iq cloud affected >= 4.0.0, <= 4.5.0 fixed ?
- vendor:f5 big-iq cloud and orchestration affected = 1.0.0 fixed ?
- vendor:f5 big-iq device affected >= 4.2.0, <= 4.5.0 fixed ?
- vendor:f5 big-iq security affected >= 4.0.0, <= 4.5.0 fixed ?
- vendor:Linux Kernel affected ? fixed ?

## How to check

uname -r to see the running kernel version; compare against the kernel release that carries the 2014 n_tty fix (unknown from sources)

## Fix

Update to a patched Linux kernel from your distribution; the sources do not name the fixed version.
If the kernel is end-of-life and cannot be patched, CISA says to disconnect it from use.

## Timeline

- 2026-10-23T19:11:52+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2014-0196
- 2026-10-23T22:29:04+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2014-0196

## From the sources

The n_tty_write function in drivers/tty/n_tty.c in the Linux kernel through 3.14.3 does not properly manage tty driver access in the "LECHO & !OPOST" case, which allows local users to cause a denial of service (memory corruption and system crash) or gain privileges by triggering a race condition involving read and write operations with long strings.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_