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CVE-2019-0054

An Improper Certificate Validation weakness in the SRX Series Application Identification (app-id) signature update clien

An Improper Certificate Validation weakness in the SRX Series Application Identification (app-id) signature update client of Juniper Networks Junos OS allows an attacker to perform Man-in-the-Middle (MitM) attacks which may compromise the integrity and confidentiality of the device. This issue affects: Juniper Networks Junos OS 15.1X49 versions prior to 15.1X49-D120 on SRX Series devices. No other versions of Junos OS are affected.

MEDIUM · CVSS 6.8 EPSS 0.00587
EPSS exploitation odds0.59% · top 56%
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
No Sigma yet — build one → YARA rules0
Look this up elsewhere - one-click external pivots
NVDCVE.orgCISAExploit-DBGitHub PoCVulnCheck KEVGreyNoise
▸ How to read a CVE - triage first, then detect and patch
This page is every public fact about CVE-2019-0054, cross-linked. Its job is to answer one question fast - does this need my attention now? - and then hand you the two things you do about it. Here is how an analyst reads it.
Triage: should I act now? Four signals, and they are not interchangeable:
CVSSseverity - how bad it is IF exploited, 0-10. A high CVSS alone is not urgency; a flaw can be a perfect 10 and never actually be attacked. EPSSprobability - a model’s estimate of the chance it is exploited in the next 30 days, 0-1. This is the “will it actually happen” signal. CISA KEVconfirmed - it is being exploited in the wild right now. The strongest signal on the page; KEV beats any score. Weaponisedavailability - public exploits / PoCs, and especially Metasploit modules rated Excellent / Great. Reliable, packaged exploit code means low-skill attackers can use it today.
How they combine: KEV, or a dependable Metasploit module, means patch now regardless of CVSS. High CVSS + low EPSS + no exploit is real but not an emergency - schedule it. Low CVSS but KEV-listed still gets patched now. The verdict above already weighed these for you; this is how it got there.
Then what - two workflows:
Detectwhen you cannot patch today, follow this CVE to the ATT&CK techniques it enables, then Build a SIEM detection (the green button) - author a rule, test it in Atomic, deploy it. That buys visibility while the patch waits. PatchAffected products / packages tell you if you are exposed; Fixed versions by distribution and Vendor advisories give the exact version that closes it.
Reading order for the panels below: verdict + badges, then Public exploits / Metasploit (is it weaponised), then ATT&CK techniques + Sigma / IDS rules (can I detect it), then Affected products / packages + Fixed versions (am I exposed, what patches it), then Threat actors / IOCs (who uses it), then Scoring & timeline / references (the evidence).
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Exploitation momentum

7 days of EPSS
dormant
Flat and low - no real exploitation pressure. This reads the direction and speed of EPSS over time, which can move before EPSS itself peaks or before CISA lists it.
Window
▣

Severity & exploitation scoring

View on NVD →
CVSS base score
6.8
MEDIUMCVSS v3.1 · [email protected]
EPSS exploitation probability
0.59%
Top 56%odds of exploitation in the next 30 days
CVSS metric silhouette
VectorComplexityPrivilegesInteractionScopeConfidentialityIntegrityAvailability
shape grows toward worst-case
SSVC triage
No SSVC vulnrichment for this CVE. CISA's Vulnrichment program scores newer CVEs (~2024 onwards) plus selected older critical ones. Use the EPSS probability + KEV status to triage instead.
CVSS vector breakdown
Exploitability - how they get in
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Impact - what breaks
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
VECTORCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
Lifecycle
  1. 09 Oct 2019Published to NVD
  2. 17 Jun 2026Last modified
Every entry is a recorded date - NVD publish/modify, CISA KEV add, public exploit disclosure. No inferred events.
Attack path
Full kill chain
→
◆

ATT&CK techniques

2

Techniques this CVE enables. Pills with a solid outline are high confidence - named directly in ATT&CK or Nuclei, or human-curated by CTID; the rest are inferred from the weakness type using MITRE's CVE Mapping Methodology and the CWE → CAPEC chain. Broad, generic-weakness guesses are filtered out. A small N× marks a technique that N independent sources agree on.

T1203 · Exploitation for Client Execution T1566 · Phishing
▤ Build a SIEM detection for these techniques
▤

CAPEC attack patterns

11

Attack patterns this CVE enables - the bridge from weakness to ATT&CK technique.

CAPEC-CAPEC-459 · Creating a Rogue Certification Authority Certificate CAPEC-CAPEC-466 · Leveraging Active Adversary in the Middle Attacks to Bypass Same Origin Policy CAPEC-CAPEC-475 · Signature Spoofing by Improper Validation CAPEC-CAPEC-57 · Utilizing REST's Trust in the System Resource to Obtain Sensitive Data CAPEC-CAPEC-589 · DNS Blocking CAPEC-CAPEC-590 · IP Address Blocking CAPEC-CAPEC-612 · WiFi MAC Address Tracking CAPEC-CAPEC-613 · WiFi SSID Tracking CAPEC-CAPEC-615 · Evil Twin Wi-Fi Attack CAPEC-CAPEC-662 · Adversary in the Browser (AiTB) CAPEC-CAPEC-94 · Adversary in the Middle (AiTM)
⬡

Weakness Classification

CWE-295Improper Certificate Validation
CWE-295Improper Certificate Validation
CWE-300Channel Accessible by Non-Endpoint
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Affected Products & Versions

1
juniper junosall versions
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Related CVEs

8
CVEs linked to this one by a shared weakness (CWE) or affected product - joins on data already in the engine, with the reason shown per row.
CVE-2002-0862 The (1) CertGetCertificateChain, (2) CertVerifyCertificateChainPolicy, and (3) W... 1 same CWE-295 CVE-2003-1229 X509TrustManager in (1) Java Secure Socket Extension (JSSE) in SDK and JRE 1.4.0... same CWE-295 CVE-2005-3170 The LDAP client on Microsoft Windows 2000 before Update Rollup 1 for SP4 accepts... same CWE-295 MEDIUM CVE-2006-7246 NetworkManager 0.9.x does not pin a certificate's subject to an ESSID when 802.1... same CWE-295 MEDIUM CVE-2016-10536 engine.io-client is the client for engine.io, the implementation of a transport-... same CWE-300 MEDIUM CVE-2017-6052 A Man-in-the-Middle issue was discovered in Hyundai Motor America Blue Link 3.9.... same CWE-300 LOW CVE-2017-7480 rkhunter versions before 1.4.4 are vulnerable to file download over insecure cha... same CWE-300 CRITICAL CVE-2017-6870 A vulnerability was discovered in Siemens SIMATIC WinCC Sm@rtClient for Android ... same CWE-300 HIGH
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References & Sources

2
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://kb.juniper.net/JSA10952
Vendor Advisory
https://www.juniper.net/documentation/en_US/junos/topics/topic-map/security-application-identification-overview.html
Vendor Advisory
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