Resource Exhaustion Affecting localstack package, versions <4.14.0-r18


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.16% (6th percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-LOCALSTACK-17908789
  • published9 Jul 2026
  • disclosed17 Jun 2026

Introduced: 17 Jun 2026

CVE-2026-48990  (opens in a new tab)
CWE-400  (opens in a new tab)
CWE-770  (opens in a new tab)

How to fix?

Upgrade Chainguard localstack to version 4.14.0-r18 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream localstack package and not the localstack package as distributed by Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

joserfc is a Python library that provides an implementation of several JSON Object Signing and Encryption (JOSE) standards. In versions 1.3.4 through 1.6.5, joserfc accepts oversized RFC7797 b64=false JWS payloads without applying JWSRegistry.max_payload_length, which can lead to resource exhaustion. The normal JWS compact and flattened JSON paths reject payloads above the configured payload-size limit with ExceededSizeError. The RFC7797 unencoded payload paths do not make the same check. A valid b64=false compact or flattened JSON JWS can therefore deserialize successfully with a payload larger than JWSRegistry.max_payload_length. Applications that accept lower-trust JWS values and rely on joserfc to reject oversized token content during verification have a moderate availability risk. This issue has been fixed in version 1.6.7.

CVSS Base Scores

version 3.1