Auth bypass in Juniper Screenos

CVE-2015-7755

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.

Vulnerability class: Broken Authentication

EPSS: 0.614 (99.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on . CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: .

Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2015-7755?
CVE-2015-7755 is a critical-severity vulnerability in Juniper Screenos, classified under Improper Authentication. CVSS score: 9.8/10. Published 2015-12-19.
How severe is CVE-2015-7755?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2015-7755 known to be exploited?
Yes. CVE-2015-7755 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-10-02), indicating it is being actively exploited. 23 public proof-of-concept repositories are indexed.