CVE-2026-124740 (GCVE-0-2026-124740)
Vulnerability from cvelistv5 – Published: 2026-11-11 11:19 – Updated: 2026-11-12 19:34
VLAI
EPSS
VEX
Title
Busybox: use-after-free of requested_ipv6 in udhcpc6
Summary
A flaw was found in BusyBox's udhcpc6 DHCPv6 client. A malicious server on the local network can trigger a use-after-free condition by responding with a crafted Dynamic Host Configuration Protocol for IPv6 (DHCPv6) reply packet lacking usable address options. This issue causes the client to read stale heap memory, which can result in a Denial of Service (DoS) due to an application crash or disclose previously assigned network address data in subsequent discovery requests.
Severity
4.3 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-12 19:33 UTC
CWE
- CWE-416 - Use After Free
Assigner
redhat
CNA
References
2 references
| URL | Tags |
|---|---|
| https://access.redhat.com/security/cve/CVE-2026-124740 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2571616 | issue-trackingx_refsource_REDHAT |
Impacted products
2 products
| Vendor | Product | Version | |
|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 6 |
cpe:/o:redhat:rhel_els:6
|
|
| Red Hat | Red Hat Hardened Images |
cpe:/a:redhat:hummingbird:1
|
Date Public
2026-11-11 09:15
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