Vulnerability report

Exploited in the wild Confirmed confidence In CISA KEV

CVE-2020-1631

Junos OS Path Traversal

Juniper Networks / Junos OS · affected before 12.3R12-S16

Severity
CVSS 8.8 · High
Confidence
Confirmed
Exploit status
Exploited in the wild
EPSS
4.7%
First observed
Last observed

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2020-1631 is an unauthenticated vulnerability affecting Juniper Networks Junos OS. A vulnerability in the HTTP/HTTPS service used by J-Web, Web Authentication, Dynamic-VPN (DVPN), Firewall Authentication...

Is it exploited?

Yes. KEV Intelligence tracks this CVE as a known exploited vulnerability. Confidence is confirmed.

Who is affected?

Juniper Networks / Junos OS affected before 12.3r12-s16.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

Junos OS Path Traversal

A vulnerability in the HTTP/HTTPS service used by J-Web, Web Authentication, Dynamic-VPN (DVPN), Firewall Authentication Pass-Through with Web-Redirect, and Zero Touch Provisioning (ZTP) allows an unauthenticated attacker to perform local file inclusion (LFI) or path traversal. Using this vulnerability, an attacker may be able to inject commands into the httpd.log, read files with 'world' readable permission file or obtain J-Web session tokens. In the case of command injection, as the HTTP service runs as user 'nobody', the impact of this command injection is limited. (CVSS score 5.3, vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N) In the case of reading files with 'world' readable permission, in Junos OS 19.3R1 and above, the unauthenticated attacker would be able to read the configuration file. (CVSS score 5.9, vector CVSS:3.1/ AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N) If J-Web is enabled, the attacker could gain the same level of access of anyone actively logged into J-Web. If an administrator is logged in, the attacker could gain administrator access to J-Web. (CVSS score 8.8, vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) This issue only affects Juniper Networks Junos OS devices with HTTP/HTTPS services enabled. Junos OS devices with HTTP/HTTPS services disabled are not affected. If HTTP/HTTPS services are enabled, the following command will show the httpd processes: user@device> show system processes | match http 5260 - S 0:00.13 /usr/sbin/httpd-gk -N 5797 - I 0:00.10 /usr/sbin/httpd --config /jail/var/etc/httpd.conf To summarize: If HTTP/HTTPS services are disabled, there is no impact from this vulnerability.

If HTTP/HTTPS services are enabled and J-Web is not in use, this vulnerability has a CVSS score of 5.9 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N). If J-Web is enabled, this vulnerability has a CVSS score of 8.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H). Juniper SIRT has received a single report of this vulnerability being exploited in the wild. Out of an abundance of caution, we are notifying customers so they can take appropriate actions. Indicators of Compromise: The /var/log/httpd.log may have indicators that commands have injected or files being accessed. The device administrator can look for these indicators by searching for the string patterns "=*;*&" or "*%3b*&" in /var/log/httpd.log, using the following command: user@device> show log httpd.log | match "=*;*&|=*%3b*&" If this command returns any output, it might be an indication of malicious attempts or simply scanning activities. Rotated logs should also be reviewed, using the following command: user@device> show log httpd.log.0.gz | match "=*;*&|=*%3b*&" user@device> show log httpd.log.1.gz | match "=*;*&|=*%3b*&" Note that a skilled attacker would likely remove these entries from the local log file, thus effectively eliminating any reliable signature that the device had been attacked. This issue affects Juniper Networks Junos OS 12.3 versions prior to 12.3R12-S16; 12.3X48 versions prior to 12.3X48-D101, 12.3X48-D105; 14.1X53 versions prior to 14.1X53-D54; 15.1 versions prior to 15.1R7-S7; 15.1X49 versions prior to 15.1X49-D211, 15.1X49-D220; 16.1 versions prior to 16.1R7-S8; 17.2 versions prior to 17.2R3-S4; 17.3 versions prior to 17.3R3-S8; 17.4 versions prior to 17.4R2-S11, 17.4R3-S2; 18.1 versions prior to 18.1R3-S10; 18.2 versions prior to 18.2R2-S7, 18.2R3-S4; 18.3 versions prior to 18.3R2-S4, 18.3R3-S2; 18.4 versions prior to 18.4R1-S7, 18.4R3-S2 ; 18.4 version 18.4R2 and later versions; 19.1 versions prior to 19.1R1-S5, 19.1R3-S1; 19.1 version 19.1R2 and later versions; 19.2 versions prior to 19.2R2; 19.3 versions prior to 19.3R2-S3, 19.3R3; 19.4 versions prior to 19.4R1-S2, 19.4R2; 20.1 versions prior to 20.1R1-S1, 20.1R2.

Vendor Product Affected Status
Juniper Networks Junos OS Before 12.3R12-S16 Affected
Juniper Networks Junos OS Before 12.3X48-D101, 12.3X48-D105 Affected
Juniper Networks Junos OS Before 14.1X53-D54 Affected
Juniper Networks Junos OS Before 15.1R7-S7 Affected
Juniper Networks Junos OS Before 15.1X49-D211, 15.1X49-D220 Affected
Juniper Networks Junos OS Before 16.1R7-S8 Affected
Juniper Networks Junos OS Before 17.2R3-S4 Affected
Juniper Networks Junos OS Before 17.3R3-S8 Affected
Juniper Networks Junos OS Before 17.4R2-S11, 17.4R3-S2 Affected
Juniper Networks Junos OS Before 18.1R3-S10 Affected
Juniper Networks Junos OS Before 18.2R2-S7, 18.2R3-S4 Affected
Juniper Networks Junos OS Before 18.3R2-S4, 18.3R3-S2 Affected
Juniper Networks Junos OS Before 18.4R1-S7, 18.4R3-S2 Affected
Juniper Networks Junos OS Before 19.1R1-S5, 19.1R3-S1 Affected
Juniper Networks Junos OS Before 19.2R2 Affected
Juniper Networks Junos OS Before 19.3R2-S3, 19.3R3 Affected
Juniper Networks Junos OS Before 19.4R1-S2, 19.4R2 Affected
Juniper Networks Junos OS Before 20.1R1-S1, 20.1R2 Affected
Published
04 May 2020
Exploitation Reported
25 Mar 2022
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
Required

Tags

cisa windows edge

CVE References

  • CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2020-1631
  • kb.juniper.net/JSA11021 kb.juniper.net · CVE Record https://kb.juniper.net/JSA11021

Exploitation evidence

Why KEV Intelligence 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

Recorded 25 Mar 2022

Independent exploitation attestation added to the KEV Intelligence record.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the KEV Intelligence Pro API.

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Source Added
CISA First 2022-03-25 00:00 UTC

Detection

Operational artifacts and observed signals

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Observed signals

Request targets
0
User-Agents
0

Raw values available in Pro and Enterprise.

Scanner coverage

No scanner integrations recorded yet.

Virtual patch status

No KEV Intelligence 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

Timeline

From disclosure to observed exploitation

  1. Added to CISA KEV

    Listed in the CISA Known Exploited Vulnerabilities catalog

  2. CVE published

    Vulnerability disclosed publicly

  3. CVE ID reserved

    Identifier reserved by the CNA

Pro API

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  • First-party sensor telemetry
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GET /api/v2/pro/kevs/CVE-2020-1631

Free JSON includes basic KEV fields
{
  "cve_id": "CVE-2020-1631",
  "confidence": "Confirmed",
  "cvss_score": 8.8,
  "cvss_estimated": false,
  "epss_score": 0.04725,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}

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