CVE-2019-17455

Publication date 10 October 2019

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

Libntlm through 1.5 relies on a fixed buffer size for tSmbNtlmAuthRequest, tSmbNtlmAuthChallenge, and tSmbNtlmAuthResponse read and write operations, as demonstrated by a stack-based buffer over-read in buildSmbNtlmAuthRequest in smbutil.c for a crafted NTLM request.

From the Ubuntu Security Team

It was discovered that Libntlm incorrectly handled specially crafted NTML requests. An attacker could possibly use this issue to cause a denial of service or another unspecified impact.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
libntlm	22.04 LTS jammy	Not affected
	21.10 impish	Not affected
	21.04 hirsute	Not affected
	20.10 groovy	Not affected
	20.04 LTS focal	Fixed 1.5-2ubuntu0.1
	19.10 eoan	Ignored end of life
	19.04 disco	Ignored end of life
	18.04 LTS bionic	Fixed 1.4-8ubuntu0.1
	16.04 LTS xenial	Fixed 1.4-7ubuntu0.1~esm1
	14.04 LTS trusty	Fixed 1.4-1ubuntu0.1~esm1

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Notes

ebarretto

No fix available as of 2019-12-04

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
libntlm	Upstream: b967886

Severity score breakdown

Parameter	Value
Base score	9.8 · Critical
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	High
Integrity impact	High
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H