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CVE-2024-5293NVD status: Analyzed

DIR-2640: Stack-based Buffer Overflow

CVE-2024-5293 is a high-severity stack-based buffer overflow vulnerability in DIR-2640 from D-Link, with a CVSS 3.0 base score of 8.8 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. Affected DIR-2640 versions: 1.11B02_BETA02. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.61% chance of exploitation within 30 days, higher than 76% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of DIR-2640 you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
D-LinkDIR-26401.11B02_BETA02Not stated
D-Linkdir-2640_firmware1.11b02Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
AdjacentThe attacker must be on the same local network segment.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (trendmicro.com).

Official description

D-Link DIR-2640 HTTP Referer Stack-Based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of D-Link DIR-2640-US routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within prog.cgi, which handles HNAP requests made to the lighttpd webserver listening on TCP ports 80 and 443. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-21853.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Stack-based Buffer Overflow

The product writes past the end of a buffer that was allocated on the stack.

How developers prevent this class of flaw

  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND discusses canary-based detection in detail.
  • Use an abstraction library to abstract away risky APIs. Not a complete solution.
  • Implement and perform bounds checking on input.

More Stack-based Buffer Overflow vulnerabilities (CWE-121)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in DIR-2640

All DIR-2640 vulnerabilities

Recent Stack-based Buffer Overflow vulnerabilities

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