GHSA-5whh-4q9j-7v28: Aws kms tls auth Aws-kms-tls-auth Vulnerable To Memory Overallocation Vulnerability

LOW
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CVSS 3.7
CWE-119
Published
Advisory Summary

GHSA-5whh-4q9j-7v28 is a LOW (CVSS 3.7) aws-kms-tls-auth vulnerable to memory overallocation vulnerability (CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer) affecting Aws kms tls auth libraries in the crates.io ecosystem. The issue involves aws-kms-tls-auth vulnerable to memory overallocation. Remediation is available by upgrading affected packages to version 0.0.3.

GHSA-5whh-4q9j-7v28 at a Glance

CVE Identifier N/A
GHSA Identifier GHSA-5whh-4q9j-7v28
Severity LOW
CVSS v3.1 Base Score 3.7
CWE Classification CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer
Affected Product Aws kms tls auth
Package Ecosystem crates.io
Published Date
Last Updated

Security Impact

CVSS: 3.7

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

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

How to Fix GHSA-5whh-4q9j-7v28

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

aws-kms-tls-auth fixed: 0.0.3 
Upgrade aws-kms-tls-auth to 0.0.3
Verify Direct and Transitive Dependencies

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

inspect dependencies for aws-kms-tls-auth

How to Check if You Are Affected

To determine whether your application is affected by GHSA-5whh-4q9j-7v28, inspect your project dependencies for Aws kms tls auth:

inspect dependencies for aws-kms-tls-auth

Analyze the terminal output to locate any version of Aws kms tls auth in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.0.3), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer, where the product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. this may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data. In Aws kms tls auth, 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

### Summary aws-kms-tls-auth is an optional utility for s2n-tls that enables customers to use AWS KMS keys as part of the PSK extension field in a TLS 1.3 handshake. An issue exists in this library that can lead to overallocation of memory potentially resulting in a denial of service. ### Impact The PSK extension field in TLS 1.3 uses length-prefixed lists to encode variable-length data. aws-kms-tls-auth interprets the length prefix incorrectly resulting in additional memory allocation.  s2n-tls limits ClientHello messages to 64 KB. Due to this issue, the server may allocate up to 10× the received size, meaning a single message could trigger an allocation of up to 640 KB. Repeated allocations of this size could exhaust server resources and lead to a denial-of-service. No AWS services are affected. Applications should continue to follow best practices by limiting the number of in-flight handshakes and concurrent connections. Applications using the aws-kms-tls-auth crate should upgrade to version 0.0.3. **Impacted versions:** < 0.0.3 ### Patches This issue has been addressed in aws-kms-tls-auth v0.0.3 [1]. ### Workarounds There is no workaround. Applications using aws-kms-tls-auth should upgrade to the most recent release. ### Acknowledgement s2n-tls would like to thank Joshua Rogers (https://joshua.hu/) of AISLE Research Team (https://aisle.com/) for collaborating on this issue through the coordinated disclosure process. If there are any questions or comments about this advisory, contact AWS/Amazon Security via the vulnerability reporting page [2] or directly via email to [aws-security@amazon.com](mailto:aws-security@amazon.com). Please do not create a public GitHub issue. [1] https://crates.io/crates/aws-kms-tls-auth/0.0.3 [2] Vulnerability reporting page: https://aws.amazon.com/security/vulnerability-reporting

GHSA-5whh-4q9j-7v28 Affected Aws kms tls auth Versions

1 component(s)
Fixed Versions:
0.0.3
Product / Package Ecosystem Affected Versions Fixed Version
aws-kms-tls-auth
 crates.io
< 0.0.3
0.0.3

References

GitHub Advisory / Wiki ADVISORY
https://github.com/aws/s2n-tls/security/advisories/GHSA-5whh-4q9j-7v28
Aws kms tls auth Source Repository REPOSITORY
https://github.com/aws/s2n-tls

Frequently Asked Questions

What is GHSA-5whh-4q9j-7v28?
GHSA-5whh-4q9j-7v28 is a security vulnerability in Aws kms tls auth involving aws-kms-tls-auth vulnerable to memory overallocation under CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer.
Which Aws kms tls auth versions are affected?
Affected versions include releases prior to 0.0.3 across affected packages: aws-kms-tls-auth.
What version fixes GHSA-5whh-4q9j-7v28?
Upgrading to 0.0.3 (or the latest patched release for your respective branch) resolves the vulnerability.
Is aws-kms-tls-auth affected?
Yes, aws-kms-tls-auth is affected in releases prior to 0.0.3. Upgrade your dependency to 0.0.3 or later.
What is the CVSS score of GHSA-5whh-4q9j-7v28?
GHSA-5whh-4q9j-7v28 has a CVSS v3.1 base score of 3.7 (LOW) with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L.
What CWE is associated with GHSA-5whh-4q9j-7v28?
GHSA-5whh-4q9j-7v28 is classified under CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer (The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.).
How can I check crates.io dependencies for GHSA-5whh-4q9j-7v28?
Run the dependency tree command: 'inspect dependencies for aws-kms-tls-auth'. 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-5whh-4q9j-7v28",
  "modified" : "2026-03-03T20:07:00Z",
  "published" : "2026-03-03T20:07:00Z",
  "aliases" : [ ],
  "summary" : "aws-kms-tls-auth vulnerable to memory overallocation",
  "details" : "### Summary\naws-kms-tls-auth is an optional utility for s2n-tls that enables customers to use AWS KMS keys as part of the PSK extension field in a TLS 1.3 handshake. An issue exists in this library that can lead to overallocation of memory potentially resulting in a denial of service.\n\n### Impact\nThe PSK extension field in TLS 1.3 uses length-prefixed lists to encode variable-length data. aws-kms-tls-auth interprets the length prefix incorrectly resulting in additional memory allocation. \n\ns2n-tls limits ClientHello messages to 64 KB. Due to this issue, the server may allocate up to 10× the received size, meaning a single message could trigger an allocation of up to 640 KB. Repeated allocations of this size could exhaust server resources and lead to a denial-of-service.\n\nNo AWS services are affected. Applications should continue to follow best practices by limiting the number of in-flight handshakes and concurrent connections. Applications using the aws-kms-tls-auth crate should upgrade to version 0.0.3.\n\n**Impacted versions:** < 0.0.3\n\n### Patches\nThis issue has been addressed in aws-kms-tls-auth v0.0.3 [1].\n\n### Workarounds\nThere is no workaround. Applications using aws-kms-tls-auth should upgrade to the most recent release.\n\n### Acknowledgement \ns2n-tls would like to thank Joshua Rogers (https://joshua.hu/) of AISLE Research Team (https://aisle.com/) for collaborating on this issue through the coordinated disclosure process.\n\nIf there are any questions or comments about this advisory, contact AWS/Amazon Security via the vulnerability reporting page [2] or directly via email to [aws-security@amazon.com](mailto:aws-security@amazon.com). Please do not create a public GitHub issue.\n\n[1] https://crates.io/crates/aws-kms-tls-auth/0.0.3\n[2] Vulnerability reporting page: https://aws.amazon.com/security/vulnerability-reporting",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "aws-kms-tls-auth"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "0.0.3"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/aws/s2n-tls/security/advisories/GHSA-5whh-4q9j-7v28"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/aws/s2n-tls"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-119" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-03T20:07:00Z",
    "nvd_published_at" : null
  }
}