What it is
CVE-2015-7755 is an unauthenticated vulnerability affecting Juniper Networks ScreenOS. 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,...
Vulnerability report
Exploited in the wild
Confirmed confidence
In CISA KEV
CVE-2015-7755
ScreenOS
Juniper Networks / ScreenOS
- Severity
- CVSS 9.8 · Critical
- Confidence
- Confirmed
- Exploit status
- Exploited in the wild
- EPSS
- 61.1%
- First observed
- —
- Last observed
- —
Decision summary
What security teams need to know first
Direct answers before the deeper technical record.
Is it exploited?
Yes. Previdian tracks this CVE as a known exploited vulnerability. Confidence is confirmed. Listed in CISA KEV. Also confirmed by third-party sources.
Who is affected?
Juniper Networks / ScreenOS.
What should we do?
Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
Overview
ScreenOS
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.
- Published
- 19 Dec 2015
- Exploitation Reported
- 01 Jun 2026
- Attack vector
- Remote
- Complexity
- Low
- Privileges
- None
- User interaction
- None
Tags
cisa
edge
CVE References
- CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2015-7755
- VU#640184 kb.cert.org · Third-Party Advisory http://www.kb.cert.org/vuls/id/640184
- 1034489 securitytracker.com · VDB Entry http://www.securitytracker.com/id/1034489
- 79626 securityfocus.com · VDB Entry http://www.securityfocus.com/bid/79626
- arstechnica.com/security/2015/12/unauthorized-code-in-junipe... arstechnica.com · CVE Record http://arstechnica.com/security/2015/12/unauthorized-code-in-juniper-...
- wired.com/2015/12/juniper-networks-hidden-backdoors-sh... wired.com · CVE Record http://www.wired.com/2015/12/juniper-networks-hidden-backdoors-show-t...
- forums.juniper.net/t5/Security-Incident-Response/Important-Anno... forums.juniper.net · CVE Record https://forums.juniper.net/t5/Security-Incident-Response/Important-An...
- GitHub — hdm/juniper-cve-2015-7755 github.com · CVE Record https://github.com/hdm/juniper-cve-2015-7755
- kb.juniper.net/InfoCenter/index kb.juniper.net · CVE Record http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10713
- twitter.com/cryptoron/statuses/677900647560253442 twitter.com · CVE Record http://twitter.com/cryptoron/statuses/677900647560253442
- adamcaudill.com/2015/12/17/much-ado-about-juniper adamcaudill.com · CVE Record https://adamcaudill.com/2015/12/17/much-ado-about-juniper/
- forbes.com/sites/thomasbrewster/2015/12/18/juniper-says... forbes.com · CVE Record http://www.forbes.com/sites/thomasbrewster/2015/12/18/juniper-says-it...
Exploitation evidence
Why Previdian marks this CVE as exploited
Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.
Exploited in the wild
CISA
A trusted third party reported exploitation.
Known exploited vulnerability sources
Per-source evidence links for KEV attestations are available through the Previdian Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| CVE First | 2026-06-01 10:41 UTC |
| CISA | 2026-06-02 14:05 UTC |
Detection
Operational artifacts and observed signals
Make the evidence actionable in scanner, SOC, and edge-control workflows.
Observed signals
- Request targets
- User-Agents
- Callback hosts
- 0
- 0
- 0
Request targets and User-Agents available in Pro. Callback host details available in Enterprise.
Scanner coverage
No scanner integrations recorded yet.
Virtual patch status
No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.
Learn about virtual patches →No detection artifacts or sensor request patterns are available for this CVE yet.
Check back as sensor telemetry and scanner integrations are updated.
Risk and context
Severity, weaknesses, and research context
CVSS v3.1
9.8
Critical
Potential damage if exploited. Separate from whether attackers are using it.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
61.1%
Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.
Weaknesses
All CVSS Scores
CVSS v3.1
9.8
Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v2.0
10.0
High
AV:N/AC:L/Au:N/C:C/I:C/A:C
Timeline
From disclosure to observed exploitation
-
14:05 UTC
Added to CISA KEV
Listed in the CISA Known Exploited Vulnerabilities catalog
-
10:41 UTC
Added to Previdian KEV Feed
High-confidence, third-party attested exploitation
-
11:00 UTC
CVE published
Vulnerability disclosed publicly
-
00:00 UTC
CVE ID reserved
Identifier reserved by the CNA
Pro API
Automate this intelligence
Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
- Evidence confidence and provenance
- First-party sensor telemetry
- PoC and scanner references
- Affected versions and enrichment
- Automation-ready JSON delivery
GET /api/v2/pro/kevs/CVE-2015-7755
Sample API response{
"cve_id": "CVE-2015-7755",
"confidence": "Confirmed",
"cvss_score": 9.8,
"cvss_estimated": false,
"epss_score": 0.61139,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": false
},
"sensor_telemetry": { "attempts": 0, "sensors": 0 }
}