CVE-2021-28100: Netflix/Priam Temporary Directory Information Disclosure Vulnerability

MODERATE
Advisory Identifier: GHSA-f4jh-ww96-9h9j
Share
CVSS 6.2
CWE-377
Published
Advisory Summary

CVE-2021-28100 is a MODERATE (CVSS 6.2) temporary directory information disclosure vulnerability (CWE-377: Insecure Temporary File) affecting Netflix/Priam libraries in the Maven ecosystem. The issue involves temporary directory information disclosure. Remediation is available in the latest vendor maintenance releases.

CVE-2021-28100 at a Glance

CVE Identifier CVE-2021-28100
GHSA Identifier GHSA-f4jh-ww96-9h9j
Severity MODERATE
CVSS v3.1 Base Score 6.2
CWE Classification CWE-377: Insecure Temporary File
Affected Product Netflix/Priam
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 6.2

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N).

Attack Vector Local (AV:L)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2021-28100

To remediate this vulnerability, upgrade all affected Netflix/Priam dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

com.netflix.priam:priam fixed: Latest secure release 
<dependency>
    <groupId>com.netflix.priam</groupId>
    <artifactId>priam</artifactId>
    <version>Latest secure release</version>
</dependency>
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree -Dincludes=com.netflix.priam

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2021-28100, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=com.netflix.priam

Analyze the terminal output to locate any version of Netflix/Priam in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: The mvn dependency:tree -Dincludes=com.netflix.priam command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-377: Insecure Temporary File, where creating and using insecure temporary files can leave application and system data vulnerable to attack. In Netflix/Priam, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Impact When `File.createTempFile` creates a file, the permissions on that file are -rw-r--r--. This means that other users can read the contents of these files after they are written, although they can not modify the contents. This allows for local information disclosure if these files contain sensitive information. Vulnerable locations: - https://github.com/Netflix/Priam/blob/362660bb7ebddb0cfa756a282d94678f65af9f06/priam/src/main/java/com/netflix/priam/backup/MetaData.java#L106-L111 - https://github.com/Netflix/Priam/blob/362660bb7ebddb0cfa756a282d94678f65af9f06/priam/src/main/java/com/netflix/priam/identity/DoubleRing.java#L109-L118 - https://github.com/Netflix/Priam/blob/362660bb7ebddb0cfa756a282d94678f65af9f06/priam/src/main/java/com/netflix/priam/restore/PostRestoreHook.java#L80-L86 --- The custom CodeQL queries leveraged to find these this as well as their results can be found here: https://lgtm.com/query/1543383251073929777/ https://lgtm.com/query/3142895023158674709/ ## Official Disclosure https://github.com/Netflix/security-bulletins/blob/master/advisories/nflx-2021-002.md ## Fix There are no fixed versions.

CVE-2021-28100 Affected Netflix/Priam Versions

1 component(s)
Product / Package Ecosystem Affected Versions Fixed Version
com.netflix.priam:priam
maven/com.netflix.priam/priam
Maven
≤ 3.1.104

References

GitHub Advisory / Wiki ADVISORY
https://github.com/JLLeitschuh/security-research/security/advisories/GHSA-f4jh-ww96-9h9j

Frequently Asked Questions

What is CVE-2021-28100?
CVE-2021-28100 is a security vulnerability in Netflix/Priam involving Temporary Directory Information Disclosure under CWE-377: Insecure Temporary File.
Which Netflix/Priam versions are affected?
Affected versions include releases prior to current release patches across affected packages: com.netflix.priam:priam.
What version fixes CVE-2021-28100?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
Is priam affected?
Yes, com.netflix.priam:priam is affected in releases prior to Latest secure release. Upgrade your dependency to Latest secure release or later.
What is the CVSS score of CVE-2021-28100?
CVE-2021-28100 has a CVSS v3.1 base score of 6.2 (MODERATE) with vector string CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2021-28100?
CVE-2021-28100 is classified under CWE-377: Insecure Temporary File (Creating and using insecure temporary files can leave application and system data vulnerable to attack.).
How can I check Maven dependencies for CVE-2021-28100?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=com.netflix.priam'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-f4jh-ww96-9h9j",
  "modified" : "2021-03-30T16:22:43Z",
  "published" : "2021-03-30T16:23:12Z",
  "aliases" : [ "CVE-2021-28100" ],
  "summary" : "Netflix/Priam: Temporary Directory Information Disclosure",
  "details" : "### Impact\n\nWhen `File.createTempFile` creates a file, the permissions on that file are -rw-r--r--. This means that other users can read the contents of these files after they are written, although they can not modify the contents. This allows for local information disclosure if these files contain sensitive information.\n\nVulnerable locations:\n - https://github.com/Netflix/Priam/blob/362660bb7ebddb0cfa756a282d94678f65af9f06/priam/src/main/java/com/netflix/priam/backup/MetaData.java#L106-L111\n - https://github.com/Netflix/Priam/blob/362660bb7ebddb0cfa756a282d94678f65af9f06/priam/src/main/java/com/netflix/priam/identity/DoubleRing.java#L109-L118\n - https://github.com/Netflix/Priam/blob/362660bb7ebddb0cfa756a282d94678f65af9f06/priam/src/main/java/com/netflix/priam/restore/PostRestoreHook.java#L80-L86\n\n---\n\nThe custom CodeQL queries leveraged to find these this as well as their results can be found here:\n\nhttps://lgtm.com/query/1543383251073929777/\nhttps://lgtm.com/query/3142895023158674709/\n\n## Official Disclosure\n\nhttps://github.com/Netflix/security-bulletins/blob/master/advisories/nflx-2021-002.md\n\n## Fix\n\nThere are no fixed versions.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "com.netflix.priam:priam"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "3.1.104"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/JLLeitschuh/security-research/security/advisories/GHSA-f4jh-ww96-9h9j"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-377" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-03-30T16:22:43Z",
    "nvd_published_at" : "2021-03-23T21:15:00Z"
  }
}