What’s Vulnerable › Vulnerabilities

CVE-2015-7755: Juniper ScreenOS Improper Authentication Vulnerability

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: yes — in CISA KEV since 2025-10-02
• EPSS: 61.1% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2015-12-19 · updated 2026-06-17
• Weakness: CWE-287

Description

Juniper ScreenOS 6.2.0r15 through 6.2.0r18, 6.3.0r12 before 6.3.0r12b, 6.3.0r13 before 6.3.0r13b, 6.3.0r14 before 6.3.0r14b, 6.3.0r15 before 6.3.0r15b, 6.3.0r16 before 6.3.0r16b, 6.3.0r17 before 6.3.0r17b, 6.3.0r18 before 6.3.0r18b, 6.3.0r19 before 6.3.0r19b, and 6.3.0r20 before 6.3.0r21 allows remote attackers to obtain administrative access by entering an unspecified password during a (1) SSH or (2) TELNET session.

Affected products

• Juniper Networks ScreenOS: 6.3.0-r17, 6.3.0-r18, 6.3.0-r19, 6.3.0-r20

References

• http://arstechnica.com/security/2015/12/unauthorized-code-in-juniper-firewalls-decrypts-encrypted-vpn-traffic/
• http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10713
• http://twitter.com/cryptoron/statuses/677900647560253442
• http://www.forbes.com/sites/thomasbrewster/2015/12/18/juniper-says-it-didnt-work-with-government-to-add-unauthorized-code-to-network-gear/
• http://www.kb.cert.org/vuls/id/640184
• http://www.securityfocus.com/bid/79626
• http://www.securitytracker.com/id/1034489
• http://www.wired.com/2015/12/juniper-networks-hidden-backdoors-show-the-risk-of-government-backdoors/
• https://adamcaudill.com/2015/12/17/much-ado-about-juniper/
• https://forums.juniper.net/t5/Security-Incident-Response/Important-Announcement-about-ScreenOS/ba-p/285554
• https://github.com/hdm/juniper-cve-2015-7755
• http://arstechnica.com/security/2015/12/unauthorized-code-in-juniper-firewalls-decrypts-encrypted-vpn-traffic/

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