# CVE-2023-33953: PYSEC-2026-1424 - Excessive Iteration in gRPC

Source: https://junglewise.ai/threats/cve-2023-33953-excessive-iteration-in-grpc  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-07  
License: CC BY 4.0 with a link back

CVE-2023-33953 · Severity: low · CVSS 3.1 · Published 2026-07-07

Excessive Iteration in gRPC

Technologies: [grpcio (PyPI)](https://junglewise.ai/threats/technologies/grpcio), [grpc (RubyGems)](https://junglewise.ai/threats/technologies/rubygems-grpc). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi), [RubyGems](https://junglewise.ai/threats/vendors/rubygems).

## Quick answers

**Is CVE-2023-33953 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2023-33953 being exploited in the wild.

**How severe is CVE-2023-33953?** Low severity, with a CVSS score of 3.1, published 7 July 2026.

**Which products and versions are affected?** grpcio (PyPI) ECOSYSTEM:introduced=0,fixed=1.53.2, ECOSYSTEM:introduced=0,fixed=1.53.2,introduced=1.54.0,fixed=1.54.3,introduced=1.55.0,fixed=1.55.2,introduced=1.56.0,fixed=1.56.2; grpc (RubyGems) ECOSYSTEM:introduced=0,fixed=1.53.2.

**Is there a fix for CVE-2023-33953?** Yes. grpcio (PyPI): upgrade to 1.53.2, 1.56.2 or later; grpc (RubyGems): upgrade to 1.53.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2023-33953?** Check whether you run grpcio (PyPI) or grpc (RubyGems) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- grpcio (PyPI): upgrade to 1.53.2, 1.56.2 or later

  ```sh
  pip install "grpcio>=1.56.2"
  ```

- grpc (RubyGems): upgrade to 1.53.2 or later

  ```sh
  bundle update grpc
  ```


## Affected products

- grpcio (PyPI) ECOSYSTEM:introduced=0,fixed=1.53.2, ECOSYSTEM:introduced=0,fixed=1.53.2,introduced=1.54.0,fixed=1.54.3,introduced=1.55.0,fixed=1.55.2,introduced=1.56.0,fixed=1.56.2
- grpc (RubyGems) ECOSYSTEM:introduced=0,fixed=1.53.2

## Identifiers

- CVE-2023-33953
- GHSA-496j-2rq6-j6cc
- PYSEC-2026-1424

## Related threats

- [PYSEC-2026-1428 - Denial of Service Vulnerability in gRPC TCP Server (Posix-compatible platforms)](https://junglewise.ai/threats/cve-2023-4785-denial-of-service-vulnerability-in-grpc-tcp-server-posix)
- [PYSEC-2026-1426 - gRPC connection termination issue](https://junglewise.ai/threats/cve-2023-32732-grpc-connection-termination-issue)
- [PYSEC-2026-1425 - gRPC Reachable Assertion issue](https://junglewise.ai/threats/cve-2023-1428-grpc-reachable-assertion-issue)
- [PYSEC-2026-1427 - Connection confusion in gRPC](https://junglewise.ai/threats/cve-2023-32731-connection-confusion-in-grpc)
- [PYSEC-2017-101 - Google gRPC before 2017-03-29 has an out-of-bounds write caused by a heap-based use-after-free…](https://junglewise.ai/threats/cve-2017-8359-pysec-2017-101-google-grpc-before-2017-03-29-has-an-out-of-bounds)