CVE-2026-33771

High

Published: 09 April 2026

Published

09 April 2026

Modified

13 April 2026

KEV Added

—

Patch

—

CVSS Score 7.4 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

EPSS Score 0.0005 14.4th percentile

Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-33771 is a high-severity Weak Password Requirements (CWE-521) vulnerability. Its CVSS base score is 7.4 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Brute Force (T1110); ranked at the 14.4th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 IA-5 (Authenticator Management) and SI-2 (Flaw Remediation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Brute Force (T1110) and 2 other techniques. What defenders deploy: see the NIST 800-53 controls recommended below.

Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

IA-5 Authenticator Management good match

prevent

IA-5 mandates management of authenticators including establishment of sufficient strength of mechanism and complexity requirements, directly preventing the use of weak passwords due to unenforced settings.

SI-2 Flaw Remediation good match

prevent

SI-2 requires identification, reporting, and timely remediation of system flaws, directly addressing the software defect causing failure to persistently save password complexity configurations.

AC-7 Unsuccessful Logon Attempts partial match

prevent

AC-7 limits brute-force and guessing attacks on weak local account passwords by enforcing lockout after unsuccessful logon attempts.

MITRE ATT&CK Enterprise TechniquesAI

T1110 Brute Force Credential Access

Adversaries may use brute force techniques to gain access to accounts when passwords are unknown or when password hashes are obtained.

attack.mitre.org →

T1110.001 Password Guessing Credential Access

Adversaries with no prior knowledge of legitimate credentials within the system or environment may guess passwords to attempt access to accounts.

attack.mitre.org →

T1078.003 Local Accounts Stealth

Adversaries may obtain and abuse credentials of a local account as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.

attack.mitre.org →

Why these techniques?

Vulnerability allows weak passwords for local accounts due to unenforced complexity rules, directly enabling brute force and password guessing attacks (T1110.001) to obtain and abuse valid local accounts (T1078.003).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

A Weak Password Requirements vulnerability in the password management function of Juniper Networks CTP OS might allow an unauthenticated, network-based attacker to exploit weak passwords of local accounts and potentially take full control of the device. The password management menu…

enables the administrator to set password complexity requirements, but these settings are not saved. The issue can be verified with the menu option "Show password requirements". Failure to enforce the intended requirements can lead to weak passwords being used, which significantly increases the likelihood that an attacker can guess these and subsequently attain unauthorized access. This issue affects CTP OS versions 9.2R1 and 9.2R2.

Deeper analysisAI

CVE-2026-33771 is a weak password requirements vulnerability in the password management function of Juniper Networks CTP OS. The password management menu allows administrators to configure password complexity requirements, but these settings are not saved persistently. This can be verified using the "Show password requirements" menu option, resulting in the enforcement of no or minimal complexity rules. Consequently, weak passwords can be set for local accounts, increasing the risk of brute-force or guessing attacks. The vulnerability affects CTP OS versions 9.2R1 and 9.2R2, with a CVSS v3.1 base score of 7.4 (AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N) and is associated with CWE-521 (Weak Password Requirements).

An unauthenticated, network-based attacker can exploit this vulnerability by targeting local account passwords that fail to meet intended complexity standards. Due to the lack of enforced requirements, attackers may guess or brute-force these weak passwords over the network, potentially gaining unauthorized access to the device. Successful exploitation could enable full control of the affected CTP OS instance, compromising confidentiality and integrity of the system, though availability is not directly impacted.

The Juniper Networks security advisory at https://kb.juniper.net/JSA107864 details mitigation steps and available patches for this issue. Security practitioners should consult this advisory for version-specific upgrade guidance to address the persistent storage failure of password complexity settings.