CVE-2021-31352Network attack vector

Sensitive-information exposure via weak NETCONF ciphers

Published Oct 19, 2021 · Updated Sep 16, 2024

Information exposure in Juniper Networks SRC Series before 4.13.0-R6 allows remote attackers to obtain sensitive information via NETCONF over SSH. The NETCONF SSH service permits negotiation of weak ciphers, allowing an attacker with read and write access to network traffic to display plaintext bits from ciphertext blocks. Exploitation requires remote access to the NETCONF service and network data; the documented impact is sensitive-information disclosure without integrity or availability effects.

CVSS severity5.0
Medium
EPSS probability0.83%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information exposure in Juniper Networks SRC Series before 4.13.0-R6 allows remote attackers to obtain sensitive information via NETCONF over SSH. The NETCONF SSH service permits negotiation of weak ciphers, allowing an attacker with read and write access to network traffic to display plaintext bits from ciphertext blocks. Exploitation requires remote access to the NETCONF service and network data; the documented impact is sensitive-information disclosure without integrity or availability effects.

The record

CVE
CVE-2021-31352
Published
Oct 19, 2021
Updated
Sep 16, 2024
Vendor
Juniper Networks
Product
SRC Series Session and Resource Control Software
Classifications
CWE-200, CWE-327, T1040
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 19, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <4.13.0-R6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Juniper Networks · SRC Series Session and Resource Control Softwareversion=unspecified <4.13.0-R6

Published CVSS scores

5.3Juniper NetworksCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
5.0NVDAV:N/AC:L/Au:N/C:P/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
CWE-327Use of a Broken or Risky Cryptographic Algorithm
T1040Network Sniffing

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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