CVE-2026-124741
Busybox: stack buffer overflow in udhcpc6 send_d6_renew() and send_d6_release()
CVE-2026-124741 is a high vulnerability (CVSS 7.6) in Red Hat Enterprise Linux 6, published November 11, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.27%, the 20th percentile. No source names a fixed version.
- Severity
- 7.6 HighCVSS 3.1, CVE List
- Exploit chance
- 0.27%EPSS, 20th percentile
- Exploitation
- None knownNot on CISA’s or ENISA’s lists
- Fixed in
- No fix listedNo source names one
Description
A flaw was found in BusyBox. The udhcpc6 DHCPv6 client does not properly validate the size of network options sent by a server before copying them into memory. A malicious DHCPv6 server on the local network can exploit this flaw by sending a crafted reply, triggering a stack-based buffer overflow. This vulnerability could allow an attacker to achieve arbitrary code execution with root privileges or cause a denial of service (DoS) crash.
Attack profile
How easy it is to exploit
- Attack vector
- Adjacent network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- High
Exploit likelihood
Discussion
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
busyboxUbuntu:Pro:14.04:LTS | All versions, plus listed versions 1:1.20.0-8.1ubuntu11:1.20.0-9ubuntu11:1.20.0-9ubuntu21:1.21.0-1ubuntu11:1.21.0-1ubuntu1.41:1.21.0-1ubuntu1.4+esm1 | None known |
busyboxUbuntu:Pro:16.04:LTS | All versions, plus listed versions 1:1.22.0-15ubuntu11:1.22.0-15ubuntu1.41:1.22.0-15ubuntu1.4+esm11:1.22.0-15ubuntu1.4+esm2 | None known |
busyboxUbuntu:Pro:18.04:LTS | All versions, plus listed versions 1:1.22.0-19ubuntu21:1.27.2-1ubuntu31:1.27.2-1ubuntu41:1.27.2-2ubuntu21:1.27.2-2ubuntu3 Show 5 moreShow less1:1.27.2-2ubuntu3.11:1.27.2-2ubuntu3.21:1.27.2-2ubuntu3.31:1.27.2-2ubuntu3.41:1.27.2-2ubuntu3.4+esm1 | None known |
busyboxUbuntu:20.04:LTS | All versions, plus listed versions 1:1.30.1-4ubuntu41:1.30.1-4ubuntu51:1.30.1-4ubuntu61:1.30.1-4ubuntu6.11:1.30.1-4ubuntu6.21:1.30.1-4ubuntu6.31:1.30.1-4ubuntu6.41:1.30.1-4ubuntu6.5 | None known |
busyboxUbuntu:22.04:LTS | All versions, plus listed versions 1:1.30.1-6ubuntu31:1.30.1-7ubuntu11:1.30.1-7ubuntu21:1.30.1-7ubuntu31:1.30.1-7ubuntu3.1 | None known |
busyboxUbuntu:24.04:LTS | All versions, plus listed versions 1:1.36.1-3ubuntu11:1.36.1-6ubuntu11:1.36.1-6ubuntu31:1.36.1-6ubuntu3.1 | None known |
busyboxUbuntu:26.10 | All versions, plus listed versions 1:1.37.0-7ubuntu11:1.37.0-10.1ubuntu21:1.37.0-10.1ubuntu31:1.38.0-3ubuntu11:1.38.0-3ubuntu31:1.38.0-3ubuntu4 | None known |
busyboxUbuntu:26.04:LTS | All versions, plus listed versions 1:1.37.0-4ubuntu11:1.37.0-7ubuntu1 | None known |
What each source reports
CVE List Score used
Busybox: stack buffer overflow in udhcpc6 send_d6_renew() and send_d6_release()
A flaw was found in BusyBox. The udhcpc6 DHCPv6 client does not properly validate the size of network options sent by a server before copying them into memory. A malicious DHCPv6 server on the local network can exploit this flaw by sending a crafted reply, triggering a stack-based buffer overflow. This vulnerability could allow an attacker to achieve arbitrary code execution with root privileges or cause a denial of service (DoS) crash.
- Record
CVE-2026-124741- CVSS 3.1
- 7.6 High
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H - Weakness
- CWE-787
- Updated
- 2026-11-11
EUVDEUVD-2026-123349
A flaw was found in BusyBox. The udhcpc6 DHCPv6 client does not properly validate the size of network options sent by a server before copying them into memory. A malicious DHCPv6 server on the local network can exploit this flaw by sending a crafted reply, triggering a stack-based buffer overflow. This vulnerability could allow an attacker to achieve arbitrary code execution with root privileges or cause a denial of service (DoS) crash.
- Record
EUVD-2026-123349- CVSS 3.1
- 7.6 High
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H - Updated
- 2026-11-11
GitHub AdvisoriesGHSA-6p28-q7pv-rxcx
A flaw was found in BusyBox. The udhcpc6 DHCPv6 client does not properly validate the size of...
A flaw was found in BusyBox. The udhcpc6 DHCPv6 client does not properly validate the size of network options sent by a server before copying them into memory. A malicious DHCPv6 server on the local network can exploit this flaw by sending a crafted reply, triggering a stack-based buffer overflow. This vulnerability could allow an attacker to achieve arbitrary code execution with root privileges or cause a denial of service (DoS) crash.
- Record
GHSA-6p28-q7pv-rxcx- CVSS 3.1
- 7.6 High
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H - Weakness
- CWE-787
- Updated
- 2026-11-11
NVD
A flaw was found in BusyBox. The udhcpc6 DHCPv6 client does not properly validate the size of network options sent by a server before copying them into memory. A malicious DHCPv6 server on the local network can exploit this flaw by sending a crafted reply, triggering a stack-based buffer overflow. This vulnerability could allow an attacker to achieve arbitrary code execution with root privileges or cause a denial of service (DoS) crash.
- Record
CVE-2026-124741- CVSS 3.1
- 7.6 High
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H - Weakness
- CWE-787
- Updated
- 2026-11-12
OSVUBUNTU-CVE-2026-124741
A flaw was found in BusyBox. The udhcpc6 DHCPv6 client does not properly validate the size of network options sent by a server before copying them into memory. A malicious DHCPv6 server on the local network can exploit this flaw by sending a crafted reply, triggering a stack-based buffer overflow. This vulnerability could allow an attacker to achieve arbitrary code execution with root privileges or cause a denial of service (DoS) crash.
- Record
UBUNTU-CVE-2026-124741- CVSS 3.1
- 7.6 High
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H - Updated
- 2026-11-13
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, aliases, references | NVD, OSV | |
| published | EUVD, NVD | |
| published | EUVD | |
| aliases, references | GitHub Advisories | |
| aliases, published | EUVD | |
| first indexed | CVE List |
Dates are when Every CVE recorded each change. Upstream dates may differ.