CVE-2026-124740Red Hat Enterprise Linux 6 use after free
CVE-2026-124740 is a use after free in Red Hat Enterprise Linux 6, rated medium (4.3 on CVSS 3.1).
Why this priority: Medium severity, with no exploitation signal.
Published · Updated · NVD status: Awaiting Analysis
What it is
Code keeps using memory after releasing it, so an attacker who refills that memory can steer execution.
How it is reached
An attacker can exploit it from the same local network segment, without an account, and nobody has to click anything.
What an attacker gains
The direct impact is limited: partial access to data or a partial outage. In practice, this kind of flaw lets an attacker crash the process, read memory, or in the worst case run code.
Is it being exploited?
There is no public report of exploitation yet.
What to do
- No fixed version is listed yet. Find every place Red Hat Enterprise Linux 6 runs, watch the references for a fix, and plan a replacement if it is no longer supported.
- Segment the networks that can reach it.
Description from NVD
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.
What this means for your architecture.
A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.
Components it touches
- Native code: operating systems, browsers and firmware. The flaw sits wherever native code reads untrusted data.
- Network appliances and media or file parsers. The flaw sits wherever native code reads untrusted data.
Trust boundaries in play
- Local network segment. The attacker must share a network segment with the target.
- Wherever native code reads untrusted data. An attacker who crosses it can crash the process, read memory, or in the worst case run code.
Questions to answer about your own systems
- Where does Red Hat Enterprise Linux 6 run in your systems, and at which version?
- Which network segments can reach them?
- What can it reach once compromised: which data stores, secrets and services?
Read more
Issue reports
More reading
Sources
- CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
- Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
- Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
- Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.