# OSV-2023-885 - UNKNOWN READ in bytes1_char_at

Source: https://junglewise.ai/threats/osv-2023-885-unknown-read-in-bytes1-char-at-f66329ac  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2023-09-20  
License: CC BY 4.0 with a link back

Severity: info · Published 2023-09-20

UNKNOWN READ in bytes1_char_at

Technologies: [mrab-regex (PyPI)](https://junglewise.ai/threats/technologies/mrab-regex). Vendors: [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is This vulnerability exploited in the wild?** No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

**How severe is This vulnerability?** Informational severity, published 20 September 2023.

**Which products and versions are affected?** mrab-regex (PyPI) GIT:introduced=1e6986b92f978087eb34ca79732d3b0c45be8652,fixed=cdcbf36aebb0e5d54072bd96a6fe4932f1fd6ae0.

**Is there a fix for This vulnerability?** Yes. mrab-regex (PyPI): upgrade to 36aebb0e5d54072bd96a6fe4932f1fd6ae0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected?** Check whether you run mrab-regex (PyPI) 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

- mrab-regex (PyPI): upgrade to 36aebb0e5d54072bd96a6fe4932f1fd6ae0 or later

  ```sh
  pip install "mrab-regex>=36aebb0e5d54072bd96a6fe4932f1fd6ae0"
  ```


## Affected products

- mrab-regex (PyPI) GIT:introduced=1e6986b92f978087eb34ca79732d3b0c45be8652,fixed=cdcbf36aebb0e5d54072bd96a6fe4932f1fd6ae0

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- [OSV-2026-1084 - UNKNOWN READ in bytes1_char_at](https://junglewise.ai/threats/osv-2026-1084-unknown-read-in-bytes1-char-at-f9dcd088)
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- [OSV-2026-1070 - UNKNOWN READ in bytes1_char_at](https://junglewise.ai/threats/osv-2026-1070-unknown-read-in-bytes1-char-at-150dd073)