CyberSecBulletin
CVE-2024-7828NVD status: Analyzed

DNS-120: Buffer Copy without Checking Size of Input

Published Updated By the CyberSecBulletin desk

CVE-2024-7828 is a critical-severity buffer copy without checking size of input vulnerability in DNS-120 from D-Link, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected DNS-120 versions: 20240814. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 16.2% chance of exploitation within 30 days, which is in the top 3% of all scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of DNS-120 you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on supportannouncement.us.dlink.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
D-LinkDNS-12020240814Not stated
D-LinkDNR-202L20240814Not stated
D-LinkDNS-315L20240814Not stated
D-LinkDNS-32020240814Not stated
D-LinkDNS-320L20240814Not stated
D-LinkDNS-320LW20240814Not stated
D-LinkDNS-32120240814Not stated
D-LinkDNR-322L20240814Not stated
D-LinkDNS-32320240814Not stated
D-LinkDNS-32520240814Not stated
D-LinkDNS-32620240814Not stated
D-LinkDNS-327L20240814Not stated
D-LinkDNR-32620240814Not stated
D-LinkDNS-340L20240814Not stated
D-LinkDNS-34320240814Not stated
D-LinkDNS-34520240814Not stated
D-LinkDNS-726-420240814Not stated
D-LinkDNS-1100-420240814Not stated
D-LinkDNS-1200-0520240814Not stated
D-LinkDNS-1550-0420240814Not stated
D-Linkdns-726-4_firmware20240814 and earlierNot stated
D-LinkDns-120 FirmwareNot specified in the recordNot stated
D-LinkDnr-202l FirmwareNot specified in the recordNot stated
D-LinkDns-315l FirmwareNot specified in the recordNot stated
D-LinkDns-320 FirmwareNot specified in the recordNot stated

Version data comes from the organisation that assigned the CVE; 15 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 4.08.7HighCNA (vuldb.com)
CVSS 3.18.8HighCNA (vuldb.com)
CVSS 3.19.8CriticalNVD
CVSS 2.09.0HighCNA (vuldb.com)

Official description

** UNSUPPORTED WHEN ASSIGNED ** A vulnerability classified as critical was found in D-Link DNS-120, DNR-202L, DNS-315L, DNS-320, DNS-320L, DNS-320LW, DNS-321, DNR-322L, DNS-323, DNS-325, DNS-326, DNS-327L, DNR-326, DNS-340L, DNS-343, DNS-345, DNS-726-4, DNS-1100-4, DNS-1200-05 and DNS-1550-04 up to 20240814. This vulnerability affects the function cgi_set_cover of the file /cgi-bin/photocenter_mgr.cgi. The manipulation of the argument album_name leads to buffer overflow. The attack can be initiated remotely. The exploit has been disclosed to the public and may be used. NOTE: This vulnerability only affects products that are no longer supported by the maintainer. NOTE: Vendor was contacted early and confirmed that the product is end-of-life. It should be retired and replaced.

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

The underlying weakness: Buffer Copy without Checking Size of Input

The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer.

How developers prevent this class of flaw

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples include the Safe C String Library (SafeStr) by Messier and Viega, and the Strsafe.h library from Microsoft. These libraries provide safer versions of overflow-prone string-handling functions.
  • 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.

More Buffer Copy without Checking Size of Input vulnerabilities (CWE-120)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Technical write-ups (may include proof of concept)

Other references

Other vulnerabilities in DNS-120

All DNS-120 vulnerabilities

Recent Buffer Copy without Checking Size of Input vulnerabilities

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