CVE-2026-124740 (GCVE-0-2026-124740)

Vulnerability from cvelistv5 – Published: 2026-11-11 11:19 – Updated: 2026-11-11 11:19
VLAI
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)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CWE
Assigner
redhat CNA under the redhat root
CNA scorecard B 82/100 over 1197 records in the last 180 days details
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
Vendor Product Version CPE status
Red Hat Red Hat Enterprise Linux 6     cpe:/o:redhat:rhel_els:6
Create a notification for this product.
Red Hat Red Hat Hardened Images     cpe:/a:redhat:hummingbird:1
Create a notification for this product.
Date Public
2026-11-11 09:15
Credits
Red Hat would like to thank ducanhluu for reporting this issue.
Show details on NVD website
To clipboard 

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