Amazon Linux 2 : ipa, --advisory ALAS2-2026-3877 (ALAS-2026-3877)

high Nessus Plugin ID 339665

Synopsis

The remote Amazon Linux 2 host is missing a security update.

Description

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2-2026-3877 advisory.

A flaw was found in FreeIPA. When a trust relationship is configured between FreeIPA and Active Directory, Active Directory users can bypass authentication for FreeIPA services, including the portal, SMB server, and LDAP directory. This is possible by impersonating a client name in the Ticket Granting Service (TGS) due to FreeIPA services not verifying Privilege Attribute Certificate (PAC) certificates. This vulnerability could allow an authenticated Active Directory user to escalate their privileges within the FreeIPA domain. (CVE-2026-11861)

A privilege escalation flaw was found in FreeIPA. The uniqueness constraint enforced on Kerberos principal name attributes in the 389-ds directory server does not properly account for equivalent representations of the same principal name, allowing a user with sufficient LDAP write privileges to create a service principal that impersonates an existing privileged one. This can lead to unauthorized acquisition of Kerberos service tickets for sensitive services, potentially resulting in full domain compromise.
(CVE-2026-13097)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Run 'yum update ipa' or or 'yum update --advisory ALAS2-2026-3877' to update your system.

See Also

https://alas.aws.amazon.com//AL2/ALAS2-2026-3877.html

https://alas.aws.amazon.com/faqs.html

https://explore.alas.aws.amazon.com/CVE-2026-11861.html

https://explore.alas.aws.amazon.com/CVE-2026-13097.html

Plugin Details

Severity: High

ID: 339665

File Name: al2_ALAS-2026-3877.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 8/26/2026

Updated: 8/26/2026

Supported Sensors: Agentless Assessment, Continuous Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Nessus Agent, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 5

Percentile: 93.73

CVSS v2

Risk Factor: High

Base Score: 8.5

Temporal Score: 6.3

Vector: CVSS2#AV:N/AC:L/Au:S/C:C/I:C/A:N

CVSS Score Source: CVE-2026-11861

CVSS v3

Risk Factor: High

Base Score: 8.1

Temporal Score: 7.1

Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:ipa-client-common, p-cpe:/a:amazon:linux:ipa-client, p-cpe:/a:amazon:linux:ipa-common, p-cpe:/a:amazon:linux:ipa-debuginfo, p-cpe:/a:amazon:linux:ipa-python-compat, p-cpe:/a:amazon:linux:ipa-server-common, p-cpe:/a:amazon:linux:ipa-server-dns, p-cpe:/a:amazon:linux:ipa-server-trust-ad, p-cpe:/a:amazon:linux:ipa-server, p-cpe:/a:amazon:linux:python2-ipaclient, p-cpe:/a:amazon:linux:python2-ipalib, p-cpe:/a:amazon:linux:python2-ipaserver

Required KB Items: Host/local_checks_enabled, Host/AmazonLinux/release, Host/AmazonLinux/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 8/25/2026

Vulnerability Publication Date: 8/20/2026

Reference Information

CVE: CVE-2026-11861, CVE-2026-13097