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Fencer Vulns
high 7.5

CVE-2026-38753 json

A use-after-free in the awk_sub() function (editors/awk.c) of Busybox v1.38.0 allows attackers to cause a Denial of Service (DoS) via suppl…

published 2026-07-15 3 mo ago modified 2026-07-20 3 mo ago also EUVD-2026-44849

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.1%
EPSS 0.1% chance of exploitation in 30 days, percentile 3%
public exploits
0
none known

Summary

A use-after-free in the awk_sub() function (editors/awk.c) of Busybox v1.38.0 allows attackers to cause a Denial of Service (DoS) via supplying a crafted AWK script.

Patch / fix

  • busybox Debian 14 1:1.38.0-3

debian advisories DEBIAN-CVE-2026-38753

  • busybox hummingbird 1 1.37.0-8.1.hum1
  • busybox-shared hummingbird 1 1.37.0-8.1.hum1
  • busybox-petitboot hummingbird 1 1.37.0-8.1.hum1

red hat advisories RHSA-2026:41130

  • busybox SLES for SAP applications 16.0, SLES 16.0 1.37.0-160000.7.1
  • busybox SLE Module for Basesystem 15 SP7 1.37.0-150700.18.21.1
  • busybox Linux Micro 6.0 1.36.1-5.1
  • busybox SLES LTSS Extended Security 12 SP5 1.35.0-10.9.1

suse advisories SUSE-SU-2026:24154-1SUSE-SU-2026:3933-1SUSE-SU-2026:23446-1SUSE-SU-2026:3900-1

  • busybox openSUSE Leap 16.0 1.37.0-160000.7.1
  • busybox openSUSE Tumbleweed 1.38.0-2.1

opensuse advisories openSUSE-SU-2026:22040-1openSUSE-SU-2026:11605-1

  • busybox Azure Linux 3.0 1.36.1-26

azure linux advisories AZL-92832

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-38753 updated cvss 7.5

busybox: Busybox: Denial of Service via crafted AWK script in awk_sub() function

  • Red Hat Enterprise Linux 6 busybox, busybox-petitboot
    affected: workaround, no fix available “Fix deferred”
  • Red Hat Hardened Images busybox 1.37.0-8.1.hum1, busybox-shared 1.37.0-8.1.hum1, busybox-petitboot 1.37.0-8.1.hum1
    fixed: vendor fix RHSA-2026:41130

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
3 mo ago

Exploit prediction

0.14% chance of exploitation in the next 30 days, higher than 3% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 4.9 CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
CISA ADP 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

  • BusyBox BusyBox

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.