CVE-2021-29481: Ratpack session Unencrypted Storage Of Client Side Vulnerability

MODERATE
Advisory Identifier: GHSA-phj8-4cq3-794g
Share
CVSS 6.5
CWE-312
Published
Advisory Summary

CVE-2021-29481 is a MODERATE (CVSS 6.5) unencrypted storage of client side vulnerability (CWE-312: Cleartext Storage of Sensitive Information) affecting Ratpack session libraries in the Maven ecosystem. The issue involves unencrypted storage of client side sessions. Remediation is available by upgrading affected packages to version 1.9.0.

CVE-2021-29481 at a Glance

CVE Identifier CVE-2021-29481
GHSA Identifier GHSA-phj8-4cq3-794g
Severity MODERATE
CVSS v3.1 Base Score 6.5
CWE Classification CWE-312: Cleartext Storage of Sensitive Information
Affected Product Ratpack session
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 6.5

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

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

How to Fix CVE-2021-29481

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

io.ratpack:ratpack-session fixed: 1.9.0 
<dependency>
    <groupId>io.ratpack</groupId>
    <artifactId>ratpack-session</artifactId>
    <version>1.9.0</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=io.ratpack

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2021-29481, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=io.ratpack

Analyze the terminal output to locate any version of Ratpack session in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.9.0), your application is affected.

Note: The mvn dependency:tree -Dincludes=io.ratpack 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-312: Cleartext Storage of Sensitive Information, where the product stores sensitive information in cleartext within a resource that might be accessible to another control sphere. In Ratpack session, 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 The default configuration of client side sessions results in unencrypted, but signed, data being set as cookie values. This means that if something sensitive goes into the session, it could be read by something with access to the cookies. Note: the documentation does point this out and encourage users to add an encryption key, but it is not mandatory. For this to be a vulnerability, some kind of sensitive data would need to be stored in the session and the session cookie would have to leak. For example, the cookies are not configured with httpOnly and an adjacent XSS vulnerability within the site allowed capture of the cookies. The proposed change is to change the default behaviour to use a randomly generated encryption key. This would mean that sessions do not survive app restarts, but this is already the behaviour given the random signing key. ### Patches As of version 1.9.0, a securely randomly generated signing key is used. ### Workarounds Supply an encryption key, as per the documentation recommendation. ### References - https://github.com/ratpack/ratpack/pull/1590

CVE-2021-29481 Affected Ratpack session Versions

1 component(s)
Fixed Versions:
1.9.0
Product / Package Ecosystem Affected Versions Fixed Version
io.ratpack:ratpack-session
maven/io.ratpack/ratpack-session
Maven
< 1.9.0
1.9.0

References

GitHub Advisory / Wiki ADVISORY
https://github.com/ratpack/ratpack/security/advisories/GHSA-phj8-4cq3-794g
NVD — CVE-2021-29481 NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-29481
Ratpack session Source Repository REPOSITORY
https://github.com/ratpack/ratpack/pull/1590
Ratpack session Source Repository REPOSITORY
https://github.com/ratpack/ratpack

Frequently Asked Questions

What is CVE-2021-29481?
CVE-2021-29481 is a security vulnerability in Ratpack session involving Unencrypted storage of client side sessions under CWE-312: Cleartext Storage of Sensitive Information.
Which Ratpack session versions are affected?
Affected versions include releases prior to 1.9.0 across affected packages: io.ratpack:ratpack-session.
What version fixes CVE-2021-29481?
Upgrading to 1.9.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is ratpack-session affected?
Yes, io.ratpack:ratpack-session is affected in releases prior to 1.9.0. Upgrade your dependency to 1.9.0 or later.
What is the CVSS score of CVE-2021-29481?
CVE-2021-29481 has a CVSS v3.1 base score of 6.5 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2021-29481?
CVE-2021-29481 is classified under CWE-312: Cleartext Storage of Sensitive Information (The product stores sensitive information in cleartext within a resource that might be accessible to another control sphere.).
How can I check Maven dependencies for CVE-2021-29481?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=io.ratpack'. 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-phj8-4cq3-794g",
  "modified" : "2021-09-01T19:32:49Z",
  "published" : "2021-07-01T17:02:13Z",
  "aliases" : [ "CVE-2021-29481" ],
  "summary" : "Unencrypted storage of client side sessions",
  "details" : "### Impact\n\nThe default configuration of client side sessions results in unencrypted, but signed, data being set as cookie values. This means that if something sensitive goes into the session, it could be read by something with access to the cookies.\n\nNote: the documentation does point this out and encourage users to add an encryption key, but it is not mandatory.\n\nFor this to be a vulnerability, some kind of sensitive data would need to be stored in the session and the session cookie would have to leak. For example, the cookies are not configured with httpOnly and an adjacent XSS vulnerability within the site allowed capture of the cookies.\n\nThe proposed change is to change the default behaviour to use a randomly generated encryption key. This would mean that sessions do not survive app restarts, but this is already the behaviour given the random signing key.\n\n### Patches\n\nAs of version 1.9.0, a securely randomly generated signing key is used.\n\n### Workarounds\n\nSupply an encryption key, as per the documentation recommendation.\n\n### References\n\n- https://github.com/ratpack/ratpack/pull/1590\n",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "io.ratpack:ratpack-session"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.9.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/ratpack/ratpack/security/advisories/GHSA-phj8-4cq3-794g"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-29481"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ratpack/ratpack/pull/1590"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/ratpack/ratpack"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-312" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-06-30T17:48:41Z",
    "nvd_published_at" : "2021-06-29T19:15:00Z"
  }
}