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CVE-2024-20017NVD status: Analyzed

In wlan service, there is a possible out of bounds write due to improper input validation.

CVE-2024-20017 is a critical-severity improper input validation vulnerability in MT6890, MT7915, MT7916, MT7981, MT7986 from MediaTek, 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. There is no confirmed exploitation so far. EPSS estimates a 46.6% chance of exploitation within 30 days, which is in the top 1.16% of all scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of MT6890, MT7915, MT7916, MT7981, MT7986 you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on corp.mediatek.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
MediaTekMT6890, MT7915, MT7916, MT7981, MT7986Not specified in the recordNot stated
MediaTekmt6890all versionsNot stated
MediaTekmt7915all versionsNot stated
MediaTekmt7916all versionsNot stated
MediaTekmt7981all versionsNot stated
MediaTekmt7986all versionsNot stated
MediaTekSoftware Development Kit7.4.0.1 and earlier; 7.6.7.0 and earlierNot stated
OpenWrtOpenwrt19.07.0; 21.02.0Not 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
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 CISA (ADP).

Official description

In wlan service, there is a possible out of bounds write due to improper input validation. This could lead to remote code execution with no additional execution privileges needed. User interaction is not needed for exploitation Patch ID: WCNCR00350938; Issue ID: MSV-1132.

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

The underlying weakness: Improper Input Validation

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

How developers prevent this class of flaw

  • Consider using language-theoretic security (LangSec) techniques that characterize inputs using a formal language and build recognizers for that language. This effectively requires parsing to be a distinct layer that effectively enforces a boundary between raw input and internal data representations, instead of allowing parser code to be scattered throughout the program, where it could be subject to errors or inconsistencies that create weaknesses.
  • Use an input validation framework such as Struts or the OWASP ESAPI Validation API. Note that using a framework does not automatically address all input validation problems; be mindful of weaknesses that could arise from misusing the framework itself (CWE-1173).
  • Understand all the potential areas where untrusted inputs can enter the product, including but not limited to: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide data to the application. Remember that such inputs may be obtained indirectly through API calls.

More Improper Input Validation vulnerabilities (CWE-20)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in MT6890, MT7915, MT7916, MT7981, MT7986

All MT6890, MT7915, MT7916, MT7981, MT7986 vulnerabilities

Recent Improper Input Validation vulnerabilities

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