AndroidOperating system · Google

CVE-2018-9466

HIGH · 8.8 CVSS v3.1 Published 2024-11-19
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
95/100
Remediation priority · Urgent
Remotely reachable No privileges

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
In the xmlSnprintfElementContent function of valid.c, there is a possible out of bounds write. This could lead to remote escalation of privilege in an unprivileged app with no additional execution privileges needed. User interaction is needed for exploitation.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

A buffer overflow vulnerability exists in the xmlSnprintfElementContent function in libxml2's valid.c file. The function fails to properly bounds-check when writing element content to a string buffer, allowing an out-of-bounds write that can be exploited to escalate privileges in an unprivileged application through malicious XML content.

MitigationApply the libxml2 security patch for CVE-2018-9466 which adds proper bounds checking to xmlSnprintfElementContent, then rebuild and redistribute the updated library to all affected systems.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
AndroidOperating system
Affected:= 7.0= 7.1.1= 7.1.2= 8.0= 8.1

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Locate libxml2 library on the system
    Search for libxml2 shared library files (libxml2.so) in system directories such as /system/lib/, /system/lib64/, or within application bundles
    Affected if libxml2 library exists and is used by applications parsing XML content
  2. Identify the installed libxml2 version
    Run 'strings' or use a library analysis tool on the libxml2 binary to extract version information, or query the library through the application's package metadata if bundled
    Affected if The version matches Android 7.0, 7.1.1, 7.1.2, 8.0, or 8.1 system images or bundled library versions
  3. Verify the vulnerable function exists in the binary
    Analyze the libxml2 binary for the presence of the xmlSnprintfElementContent function in the valid.c component using tools like nm, objdump, or radare2
    Affected if The function symbol xmlSnprintfElementContent is present in the binary
  4. Confirm XML parsing is in use
    Review application code or runtime behavior to determine if the application parses XML documents using libxml2 APIs such as xmlParseDoc, xmlReadDoc, or related parsing functions
    Affected if The application processes untrusted XML content through libxml2 parsing functions

The environment is affected if it runs on Android 7.0 through 8.1 with a libxml2 version containing the vulnerable xmlSnprintfElementContent function that processes XML content.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply the libxml2 security patch for CVE-2018-9466 which adds proper bounds checking to xmlSnprintfElementContent, then rebuild and redistribute the updated library to all affected systems.

Recommended fix High confidence

Android 8.1 (API level 27) or later, or apply the July 2018 Android Security Patch Level

  1. 1. Check the current Android version on the affected device by navigating to Settings > About Phone > Android version
  2. 2. If the device is running Android 7.0, 7.1.1, 7.1.2, or 8.0, check if a system update is available via Settings > System > Software Update > Check for updates
  3. 3. If an update is available, download and install the latest Android security patch (this vulnerability was addressed in the July 2018 Android Security Bulletin)
  4. 4. After updating, verify the Android version has changed to 8.1 or higher, or that the security patch level reflects July 2018 or later
Caveat Upgrading Android may cause compatibility issues with older apps or custom ROMs; ensure backups are created before updating

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Android Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA3.0 h
21.0 hours of engineering $3,680
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Scan for this in your stack

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dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2018-9466 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data