CVE-2019-5188

Code execution via zero-length filename underflow

Published Jan 8, 2020 · Updated May 30, 2025

Stack out-of-bounds write in e2fsprogs e2fsck 1.43.3 through 1.45.4 allows local users to execute code via a crafted ext4 partition. During pass 3a directory rehashing, mutate_name subtracts from an unvalidated zero-length directory-entry name and writes before the new_name stack buffer. Exploitation requires control of an ext4 filesystem image and execution of e2fsck against it; successful exploitation runs code with the checker process privileges.

CVSS severity7.5
High
EPSS probability1.03%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack out-of-bounds write in e2fsprogs e2fsck 1.43.3 through 1.45.4 allows local users to execute code via a crafted ext4 partition. During pass 3a directory rehashing, mutate_name subtracts from an unvalidated zero-length directory-entry name and writes before the new_name stack buffer. Exploitation requires control of an ext4 filesystem image and execution of e2fsck against it; successful exploitation runs code with the checker process privileges.

The record

CVE
CVE-2019-5188
Published
Jan 8, 2020
Updated
May 30, 2025
Vendor
E2fsprogs Project
Product
e2fsprogs
Classifications
CWE-787
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Jan 8, 2020CVE publishedPublication date reported by the CVE source.
  2. May 30, 2025Record 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=1.43.3 - 1.45.4

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

E2fsprogs Project · e2fsprogsversion=1.43.3 - 1.45.4

Published CVSS scores

4.4NIST NVDAV:L/AC:M/Au:N/C:P/I:P/A:P
6.7NIST NVDCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
7.5Cisco TalosCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H

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)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write

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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