CVE-2021-37326Public exploitNetwork attack vector

Command execution via bracketed-paste terminator injection

Published Aug 15, 2021 · Updated Aug 4, 2024

Command injection in NetSarang Xshell 7 before Build 0077 allows context-dependent attackers to execute commands through pasted text. A leading ESC[201~ sequence prematurely closes bracketed paste mode, so the remaining pasted line reaches the connected shell as executable input. Execution requires a user to copy attacker-controlled content and paste it into a terminal session with bracketed paste mode enabled; the injected command runs with that session's remote privileges.

CVSS severity5.3
Medium
EPSS probability0.79%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Command injection in NetSarang Xshell 7 before Build 0077 allows context-dependent attackers to execute commands through pasted text. A leading ESC[201~ sequence prematurely closes bracketed paste mode, so the remaining pasted line reaches the connected shell as executable input. Execution requires a user to copy attacker-controlled content and paste it into a terminal session with bracketed paste mode enabled; the injected command runs with that session's remote privileges.

The record

CVE
CVE-2021-37326
Published
Aug 15, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-200, T1059, T1204
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 15, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.0NIST NVDAV:N/AC:L/Au:N/C:P/I:N/A:N
5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/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 exploitPublished

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
T1059Command and Scripting Interpreter
T1204User Execution

Public exploit references

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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