Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
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AccessObtain local shell access on target system
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ExploitInvoke busybox wget with crafted -T argument
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ExecutionTrigger null pointer dereference in getopt32 option handler
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ImpactCrash wget process
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A10:2025 - Mishandling of Exceptional Conditions
ASVS 5.0
V16 - Security Logging and Error Handling Null pointer safety, defensive checks
MITRE ATT&CK
1 technique across 1 tactic: Impact The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Exploitation Conditions | Exploitation requires local shell access to a system running BusyBox 1.30.0 or 1.30.1 with FEATURE_WGET_TIMEOUT enabled at compile time. The attacker must be able to invoke the BusyBox wget applet and supply a -T argument value that causes the null pointer dereference when getopt32 processes the timeout option without a valid destination pointer. Systems where BusyBox was compiled without FEATURE_WGET_TIMEOUT are not vulnerable to this specific code path. CVSS PR:L confirms that at minimum local authentication or access is required; unauthenticated remote exploitation is not possible. The impact ceiling is a crash of the wget process only - no privilege escalation path has been identified. Factors limiting real-world exploitation: attacker must have existing local account access, the impact does not extend beyond the wget process, and many embedded BusyBox deployments are on versions outside the confirmed 1.30.0-1.30.1 window. |
| Impact | The CVSS 4.0 base score of 1.9 (AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N) accurately captures the constrained impact: local access is required, confidentiality and integrity are wholly unaffected, and the only outcome is a low-severity crash of the wget process itself rather than the host. The E:P supplemental metric is set, consistent with the publicly disclosed proof-of-concept. This CVE is absent from the CISA KEV catalog, and no EPSS score was included in the source intelligence - exploitation probability is therefore unquantified but expected to be low given the local-only vector and trivial impact. Even a mid-sized municipal IT team in koszalin managing embedded BusyBox deployments would reasonably classify this as low-priority patching: an attacker must already hold local shell access, and the blast radius is limited to crashing wget rather than gaining elevated privileges or exfiltrating data. The main concern is multi-tenant embedded environments - shared IoT firmware, minimal container base images - where untrusted local users exist; in such contexts the patch should still be applied during the next maintenance cycle but warrants no emergency response. |
| Exploit ScenarioDerived | A local user with shell access on an embedded Linux system - such as an IoT device, router, or Alpine-based container - running BusyBox 1.30.0 or 1.30.1 invokes wget with a crafted -T argument that triggers the null pointer dereference in the getopt32 timeout option handler, immediately crashing the wget process. A public proof-of-concept is available at https://gist.github.com/wyxstarry/5c199ec824928c5ae5816aaecbc6df03, lowering the skill threshold for reproduction. The practical impact is limited to disrupting wget - no code execution or privilege escalation has been demonstrated. |
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Alert meAnalysisAIv1 – Aug 19, 2026
BusyBox wget's FEATURE_WGET_TIMEOUT handler in networking/wget.c crashes with a null pointer dereference when the -T (timeout) argument is processed, affecting versions 1.30.0 and 1.30.1. Local users who can invoke BusyBox wget can trigger a denial-of-service crash of the wget process by supplying a crafted -T argument value, exploiting an unguarded pointer dereference in the shared getopt32 option-parsing library. No public exploit has confirmed active production exploitation, but a public proof-of-concept is available and the CVE is not listed in CISA KEV.
RemediationAI
Apply upstream patch commit 83a40bf7a93c8ac093d33ab452222dd5b9eb57ff available at https://github.com/mirror/busybox/commit/83a40bf7a93c8ac093d33ab452222dd5b9eb57ff, which adds a null guard in libbb/getopt32.c before dereferencing on_off->optarg. Upstream fix available (PR/commit); a released patched version number is not independently confirmed from the available intelligence - verify with your BusyBox distribution or vendor for a packaged release incorporating this commit. As a compensating control, rebuild BusyBox with FEATURE_WGET_TIMEOUT disabled, which removes the vulnerable code path entirely at the cost of eliminating wget's -T timeout functionality - acceptable in environments where timeout control is unused. Alternatively, restrict local user permissions to execute BusyBox wget on affected systems to reduce exposure. Refer to the NVD advisory at https://nvd.nist.gov/vuln/detail/CVE-2026-76014 and the VulDB entry at https://vuldb.com/vuln/391923 for further tracking.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 1 package in euvd
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
BusyBox is a single multi-call binary that bundles many standard Unix utilities for embedded and minimal Linux environments. The vulnerability lies in networking/wget.c within the FEATURE_WGET_TIMEOUT compile-time feature, which enables the -T argument for controlling download timeouts. The root cause (CWE-476: NULL Pointer Dereference) traces to libbb/getopt32.c, where the code unconditionally dereferenced on_off->optarg - the destination pointer for storing parsed option values - without first verifying it was non-null. The upstream fix at commit 83a40bf introduces an explicit null guard: it first calls xatoi_positive(optarg) into a local variable n, then conditionally assigns to *(unsigned*)(on_off->optarg) only if the pointer is non-null. Affected CPE is cpe:2.3:a:n/a:busybox:*:*:*:*:*:*:*:* covering versions 1.30.0 and 1.30.1 per EUVD and NVD.
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Severity by source
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
Local vector and low privileges required to invoke wget; sole impact is a process-level crash with no confidentiality or integrity effect.
Primary rating from Vendor (VulDB).
CVSS VectorVendor: VulDB
Lifecycle Timeline
3DescriptionCVE.org
A vulnerability has been found in BusyBox up to 1.30.1. This vulnerability affects unknown code of the file networking/wget.c of the component FEATURE_WGET_TIMEOUT Handler. Such manipulation of the argument -T leads to null pointer dereference. Local access is required to approach this attack. The exploit has been disclosed to the public and may be used. The name of the patch is 83a40bf7a93c8ac093d33ab452222dd5b9eb57ff. A patch should be applied to remediate this issue.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
A null pointer dereference occurs when a program attempts to access memory through a pointer that has been set to NULL (address 0x0).
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Heap-based buffer overflow in the DHCP client (udhcpc) in BusyBox before 1.25.0 allows remote attackers to have unspecif
In the add_match function in libbb/lineedit.c in BusyBox through 1.27.2, the tab autocomplete feature of the shell, used
Integer overflow in the DHCP client (udhcpc) in BusyBox before 1.25.0 allows remote attackers to cause a denial of servi
BusyBox through 1.35.0 allows remote attackers to execute arbitrary code if netstat is used to print a DNS PTR record's
BusyBox wget thru 1.3.7 accepted raw CR (0x0D)/LF (0x0A) and other C0 control bytes in the HTTP request-target (path/que
A use-after-free in Busybox 1.35-x's awk applet leads to denial of service and possibly code execution when processing a
An issue was discovered in BusyBox through 1.30.0. Rated high severity (CVSS 7.5), this vulnerability is remotely exploi
util-linux/mdev.c in BusyBox before 1.21.0 uses 0777 permissions for parent directories when creating nested directories
Network-reachable BLU-IC2 and BLU-IC4 devices running firmware through 1.19.5 embed BusyBox 1.31.1 and are exposed to mu
An attacker-controlled pointer free in Busybox's hush applet leads to denial of service and possible code execution when
BusyBox project BusyBox wget version prior to commit 8e2174e9bd836e53c8b9c6e00d1bc6e2a718686e contains a Buffer Overflow
A heap-buffer-overflow was discovered in BusyBox v.1.36.1 in the next_token function at awk.c:1159. Rated medium severit
EUVD-2026-62225
GHSA-xwfg-2qxj-cwwg
NVD
CVE.org
EPSS
VulDB
Exploit-DB