CISA KEV catalog
Confirmed active exploitation.
Listed in CISA's catalog of Known Exploited Vulnerabilities: attackers are using it in real attacks. Patch it with priority.
- Name
- Juniper ScreenOS Improper Authentication Vulnerability
- Added to catalog
- Remediation due date (US federal)
- 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.
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: screenos
References10
- kb.juniper.net/InfoCenter/index?page=content&id=JSA10713 ExploitVendor Advisory
- forums.juniper.net/t5/Security-Incident-Response/Important-Anno… Vendor Advisory
- kb.juniper.net/InfoCenter/index?page=content&id=JSA10713 ExploitVendor Advisory
- forums.juniper.net/t5/Security-Incident-Response/Important-Anno… Vendor Advisory
- arstechnica.com/security/2015/12/unauthorized-code-in-juniper-f… Third Party Advisory
- twitter.com/cryptoron/statuses/677900647560253442 Broken Link
- www.forbes.com/sites/thomasbrewster/2015/12/18/juniper-says-it-… Permissions Required
- www.kb.cert.org/vuls/id/640184 Third Party Advisory
- www.securityfocus.com/bid/79626 Broken Link
- www.securitytracker.com/id/1034489 Broken Link
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 61% percentile: 99 · as of 8 November 2026
- CWE
- CWE-287
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