CVE-2019-25741Public exploitNetwork attack vectorHinoki check available

Code execution via session username buffer overflow

Published Jun 4, 2026 · Updated Jun 4, 2026

SEH-based buffer overflow in MobaXterm 12.1 allows context-dependent attackers to execute code through a crafted session file. The session parser copies an oversized username value without a sufficient bounds check, overwriting SEH control data used to redirect execution. The file must be imported and its malicious session opened, after which the payload runs with the MobaXterm user's privileges.

CVSS severity9.3
Critical
EPSS probability0.64%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

SEH-based buffer overflow in MobaXterm 12.1 allows context-dependent attackers to execute code through a crafted session file. The session parser copies an oversized username value without a sufficient bounds check, overwriting SEH control data used to redirect execution. The file must be imported and its malicious session opened, after which the payload runs with the MobaXterm user's privileges.

The record

CVE
CVE-2019-25741
Published
Jun 4, 2026
Updated
Jun 4, 2026
Vendor
Mobatek
Product
MobaXterm
Classifications
CWE-120, T1204.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 4, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 4, 2026Record 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=12.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mobatek · MobaXtermversion=12.1

Published CVSS scores

9.8VulnCheckCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.3VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA: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.

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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-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
T1204.002User Execution: Malicious File

Public exploit references

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Technologies

Your stack

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Your stack

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