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CVE-2018-0824Exploited in the wildNVD status: Analyzed

Microsoft COM for Windows Deserialization of Untrusted Data

CVE-2018-0824 is a high-severity deserialization of untrusted data vulnerability in windows_10 from Microsoft, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected windows_10 versions: 1607; 1703; 1709, and others listed below. The record does not name a fixed version, so check the vendor advisory. CISA added it to the Known Exploited Vulnerabilities catalogue on August 5, 2024, which means attacks have been observed in the wild.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Check which version of windows_10 you run against the affected versions below, and install the vendor's latest release.
  2. CISA's required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
  3. Read the advisory on portal.msrc.microsoft.com for workarounds and exact fixed builds.
  4. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  5. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
Microsoftwindows_101607; 1703; 1709; 1803; all versionsNot stated
Microsoftwindows_7all versionsNot stated
Microsoftwindows_8.1all versionsNot stated
Microsoftwindows_rt_8.1all versionsNot stated
Microsoftwindows_server_2008r2; all versionsNot stated
Microsoftwindows_server_2012all versions; r2Not stated
Microsoftwindows_server_20161709; 1803; all versionsNot stated
MicrosoftWindows 10 1507Not specified in the recordNot stated
MicrosoftWindows 10 1607Not specified in the recordNot stated
MicrosoftWindows 10 1703Not specified in the recordNot stated
MicrosoftWindows 10 1709Not specified in the recordNot stated
MicrosoftWindows 10 1803Not specified in the recordNot stated
MicrosoftWindows Server 1709Not specified in the recordNot stated
MicrosoftWindows Server 1803Not specified in the recordNot 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
RequiredA user must take an action such as opening a file or link.
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:R/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.8HighNVD
CVSS 3.17.5HighCISA (ADP)
CVSS 2.05.1MediumNVD

Official description

A remote code execution vulnerability exists in "Microsoft COM for Windows" when it fails to properly handle serialized objects, aka "Microsoft COM for Windows Remote Code Execution Vulnerability." This affects Windows 7, Windows Server 2012 R2, Windows RT 8.1, Windows Server 2008, Windows Server 2012, Windows 8.1, Windows Server 2016, Windows Server 2008 R2, Windows 10, Windows 10 Servers.

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

The underlying weakness: Deserialization of Untrusted Data

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

How developers prevent this class of flaw

  • If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
  • When deserializing data, populate a new object rather than just deserializing. The result is that the data flows through safe input validation and that the functions are safe.
  • Explicitly define a final object() to prevent deserialization.

More Deserialization of Untrusted Data vulnerabilities (CWE-502)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: total).
  3. Added to CISA's Known Exploited Vulnerabilities catalogue.
  4. Deadline for US federal agencies to remediate, set by CISA.
  5. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Technical write-ups (may include proof of concept)

Recent Deserialization of Untrusted Data vulnerabilities

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