VulnTideExploited vulnerabilities, by vendor. Data as of 28 Oct 2026.
Known exploitedIn CISA's KEV catalog since 2 October 2025Ransomware use: unknown
Juniper ScreenOS

CVE-2015-7755: Juniper ScreenOS Improper Authentication Vulnerability

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 2 Oct 2025, 3,575 days after the CVE record was published.

How likely is exploitation in the next 30 days?
61.1%

EPSS score, percentile 99.2 of all scored records

How severe?
9.8 Critical

CVSS v3.1 base score, from CISA's enrichment of the record

What should I do?

Required action (CISA), due 23 Oct 2025: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

The CVE record links no vendor advisory, patch or mitigation.

Which versions are affected?

Not stated. The CVE record gives vendor and product as “n/a” and the version as “unspecified”.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

What to do

Required action, set by CISA

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

CISA due date for this action: 23 October 2025.

Advisories and patches

The CVE record links no vendor advisory, patch or mitigation.

Linked from CISA's catalog entry

Affected products and versions

The CVE record does not name affected products or versions: vendor and product are “n/a” and the version is “unspecified”.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

About this vulnerability

Juniper ScreenOS contains an improper authentication vulnerability that could allow unauthorized remote administrative access to the device.

Summary: CISA's KEV catalog, as of 28 Oct 2026.

  • CISA added CVE-2015-7755 to its Known Exploited Vulnerabilities (KEV) catalog on 2 Oct 2025.
  • CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
  • The due date CISA sets for the required action is 23 Oct 2025.
  • The CVE record was published on 19 Dec 2015, 3,575 days before it was added to KEV.
  • The CVE record carries a CVSS v3.1 base score of 9.8 (Critical), taken from CISA's enrichment of the record.
  • FIRST's EPSS model puts the probability of exploitation in the next 30 days at 61.1% (percentile 99.2), as of 28 Oct 2026.
  • CISA's SSVC assessment in the CVE record: exploitation active, automatable yes, technical impact total.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.

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.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

Weakness

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.

Timeline

DateEvent
19 Dec 2015CVE record published
2 Oct 2025Added to CISA KEV
21 Oct 2025CVE record last updated
23 Oct 2025CISA due date for the required action

References

More exploited Juniper vulnerabilities

  • CVE-2025-21590: Juniper Junos OS Improper Isolation or Compartmentalization Vulnerability (added 13 Mar 2025)
  • CVE-2023-36844: Juniper Junos OS EX Series PHP External Variable Modification Vulnerability (added 13 Nov 2023)
  • CVE-2023-36845: Juniper Junos OS EX Series and SRX Series PHP External Variable Modification Vulnerability (added 13 Nov 2023)
  • CVE-2023-36846: Juniper Junos OS SRX Series Missing Authentication for Critical Function Vulnerability (added 13 Nov 2023)
  • CVE-2023-36847: Juniper Junos OS EX Series Missing Authentication for Critical Function Vulnerability (added 13 Nov 2023)
  • CVE-2023-36851: Juniper Junos OS SRX Series Missing Authentication for Critical Function Vulnerability (added 13 Nov 2023)