Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
-
AccessGain LAN access (wired, wireless, or via pivot)
-
DeliveryCraft DHCP packet with oversized TR-111 Option 125 payload
-
ExploitBroadcast or unicast packet to DIR-895L DHCP server
-
ExecutionTrigger stack buffer overflow in sendOffer/sendACK
-
PersistOverwrite return address on stack
-
ImpactExecute arbitrary code as router daemon
Vulnerability Assessment
| Weakness |
CWE
ASVS 5.0
V15 - Secure Coding and Architecture Stack buffer bounds checking
MITRE ATT&CK
1 technique across 1 tactic: Execution The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Exploitation Conditions | Exploitation requires the attacker to be on the same Layer-2 broadcast domain as the DIR-895L router - same LAN segment, same VLAN, or connected to the router's wireless network. The attacker must be able to send DHCP packets (UDP port 67) to the router. No authentication or credentials are required. The udhcpd DHCP server service must be running, which is the factory default configuration on this device. The specific trigger is a DHCP request packet carrying a malformed TR-111 Option 125 (vendor-specific information) field. Exploitation is not directly possible from the internet without first gaining LAN access via a separate vulnerability or physical/network proximity. The Layer-2 adjacency requirement is the primary factor limiting exploitation scale relative to the raw CVSS impact scores. |
| Impact | The CVSS 4.0 base score of 8.6 with E:P (exploit publicly available) accurately reflects meaningful risk given the public PoC. The AV:A (adjacent network) constraint is the primary limiting factor - exploitation requires Layer-2 network presence, meaning internet-based opportunistic attackers cannot directly trigger this flaw without first obtaining a LAN foothold. No authentication is required (PR:N), and the flaw is in the default DHCP service. The SC:H/SI:H/SA:H subsequent-system impact metrics reflect that full router compromise gives an attacker complete control over LAN routing, DNS, and traffic interception. The absence of a vendor patch substantially elevates real-world risk, particularly given that this is a legacy consumer device unlikely to receive a firmware fix. EPSS data was not provided in the input. The combination of public PoC, no patch, and AV:A scope makes this a realistic priority for defenders who have DIR-895L A1 devices on their networks, even though the adjacency requirement prevents mass internet-scale exploitation. |
| Exploit ScenarioDerived | An attacker with access to the same local network as the DIR-895L - via a compromised LAN host, rogue wired connection, or unauthorized wireless access - sends a crafted DHCP discovery packet containing a malformed TR-111 Option 125 payload with an oversized vendor-specific information field. The udhcpd daemon's sendOffer() function processes the option without adequate bounds checking, overflowing a stack buffer and overwriting the saved return address. Upon function return, execution redirects to attacker-controlled code, achieving arbitrary code execution as the DHCP daemon process. The published Notion writeup confirms this exploitation path is documented and reproducible. |
Get an e-mail when this CVE is exploited, patched or re-scored. Free account.
Alert meAnalysisAIv1 – Sep 08, 2026
Stack-based buffer overflow in D-Link DIR-895L router (firmware A1_102b07) affects the udhcpcd DHCP server daemon's sendOffer() and sendACK() functions when parsing TR-111 Option 125 vendor-specific data. An adjacent-network unauthenticated attacker can send a crafted DHCP packet to trigger the overflow, potentially achieving arbitrary code execution on the router with daemon-level privileges. A public proof-of-concept exploit has been published targeting this exact vector, and no vendor patch has been identified for this legacy device.
RemediationAI
No vendor-released patch has been identified at time of analysis. The DIR-895L A1 is a legacy D-Link product that may be past its supported lifecycle - verify current support status directly with D-Link at https://www.dlink.com/. If the device cannot be replaced, the most effective compensating control is to disable the built-in DHCP server and migrate DHCP service to a separate, supported device (trade-off: requires reconfiguration of network infrastructure). If the DHCP server must remain enabled, restrict Layer-2 access to the router using 802.1X port-based authentication or VLAN segmentation to limit which hosts can send DHCP packets to the device (trade-off: requires managed switch infrastructure). Wireless network isolation (client isolation mode) can prevent wireless clients from targeting the router's DHCP service from each other, though it does not protect against wired LAN attackers. Long-term, device replacement with a currently supported router model is the recommended resolution given the unavailability of a patch.
Affected VersionsENISA
Affects your stack
Find out whether the stacks and servers you run are on an affected version.
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
The DIR-895L runs udhcpd, a lightweight DHCP server daemon common in embedded Linux router firmware. The vulnerable code is in serverpacket.c within the sendOffer() and sendACK() functions, which construct DHCP response packets sent to clients. The public PoC exploit title ('TR-111 Option 125 Parsing') reveals that the overflow is triggered during parsing of DHCP Option 125 (vendor-encapsulated information, used in TR-111/TR-069 CPE WAN Management contexts). CWE-121 (stack-based buffer overflow) occurs when an oversized or malformed Option 125 payload is processed without adequate bounds checking, overwriting the stack frame's saved return address or adjacent function pointers. This class of flaw in DHCP server code is particularly impactful because the daemon typically runs with root or elevated privileges to bind to port 67. The affected CPE is cpe:2.3:a:d-link:dir-895l:*:*:*:*:*:*:*:*.
Know when Dir 895L gets its next vulnerability
- Watch products and get an email when something new is published
- Check this CVE against your own stack and servers
- Exploit and PoC references, threat intelligence from 22 sources
No credit card · 7-day full trial
Severity by source
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:P
Adjacent-network only (AV:A); no credentials needed (PR:N); scope change (S:C) as router compromise enables full LAN traffic interception and manipulation.
Primary rating from Vendor (VulDB).
CVSS VectorVendor: VulDB
Lifecycle Timeline
3DescriptionCVE.org
A flaw has been found in D-Link DIR-895L A1_102b07. This impacts the function sendOffer/sendACK of the file udhcpcd/serverpacket.c of the component udhcpcd. This manipulation causes stack-based buffer overflow. The attack can only be done within the local network. The exploit has been published and may be used.
Articles & Coverage 1
Technical POC Analysis
CWE-121: stack-based buffer overflow.
Full technical POC analysis - root cause, step-by-step exploitation and patch breakdown - is part of the Pro and Business plans.
Executive ViewAI
The D-Link DIR-895L router (firmware A1_102b07) contains a stack-based buffer overflow in its DHCP server daemon that enables remote code execution without requiring authentication. Publicly available exploit code exists for this vulnerability, which can be triggered from adjacent networks through specially crafted DHCP packets, potentially allowing attackers to establish persistent control of router infrastructure. Organizations running this legacy hardware face critical risk, particularly since no vendor patch has been identified and successful exploitation enables lateral movement into organizational networks.
No vendor-released patch identified at time of analysis. Implement network segmentation to restrict DHCP server access to only authorized adjacent networks; disable DHCP server functionality on vulnerable routers if static IP addressing is operationally feasible, relegating affected devices to non-critical roles only. Implement strict ACLs at boundary and internal firewalls to limit DHCP traffic scope; monitor DHCP traffic patterns for malformed Option 125 vendor-specific data; and prioritize replacement with current, actively-patched hardware from any vendor receiving regular security updates.
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 buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions.
A stack-based buffer overflow occurs when a program writes more data to a buffer located on the stack than it was allocated to hold.
An out-of-bounds write in the L2TP control-channel parsing routine (tunnel_set_params in tunnel.c) of D-Link DIR-895L fi
Command injection in the D-Link DIR-895L router's DHCP server daemon allows a network-adjacent attacker to execute arbit
EUVD-2026-72608
GHSA-xq27-3vwq-mgr2
NVD
CVE.org
EPSS
VulDB
Exploit-DB