CyberSecBulletin
CVE-2022-30024NVD status: Modified

Tl-wr841 Firmware: Buffer Copy without Checking Size of Input

CVE-2022-30024 is a high-severity buffer copy without checking size of input vulnerability in Tl-wr841 Firmware from TP-Link, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 2.04% chance of exploitation within 30 days, higher than 81% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of Tl-wr841 Firmware you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
TP-LinkTl-wr841 FirmwareNot specified in the recordNot stated
TP-LinkTl-wr841n Firmware3.16.9; 150616; 150310Not stated
TP-LinkTl-wr841n(eu) Firmware160325Not stated

Version data comes from NVD's product matching. 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
LowA basic user account is enough.
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:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Official description

A buffer overflow in the httpd daemon on TP-Link TL-WR841N V12 (firmware version 3.16.9) devices allows an authenticated remote attacker to execute arbitrary code via a GET request to the page for the System Tools of the Wi-Fi network. This affects TL-WR841 V12 TL-WR841N(EU)_V12_160624 and TL-WR841 V11 TL-WR841N(EU)_V11_160325 , TL-WR841N_V11_150616 and TL-WR841 V10 TL-WR841N_V10_150310 are also affected.

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. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in Tl-wr841 Firmware

All Tl-wr841 Firmware vulnerabilities

Recent Buffer Copy without Checking Size of Input vulnerabilities

Spotted an error? Tell us.