# CVE-2020-25659: RSA decryption vulnerable to Bleichenbacher timing vulnerability

Source: https://junglewise.ai/threats/cve-2020-25659-rsa-decryption-vulnerable-to-bleichenbacher-timing-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-01-11  
License: CC BY 4.0 with a link back

CVE-2020-25659 · Severity: low · CVSS 3.1 · Published 2021-01-11

python-cryptography 3.2 is vulnerable to Bleichenbacher timing attacks in the RSA decryption API, via timed processing of valid PKCS#1 v1.5 ciphertext.

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

## Quick answers

**Is CVE-2020-25659 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2020-25659 being exploited in the wild.

**How severe is CVE-2020-25659?** Low severity, with a CVSS score of 3.1, published 11 January 2021.

**Which products and versions are affected?** cryptography (PyPI) ECOSYSTEM:introduced=0,fixed=3.2, ECOSYSTEM:introduced=0,fixed=3.2.1.

**Is there a fix for CVE-2020-25659?** Yes. cryptography (PyPI): upgrade to 3.2, 3.2.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2020-25659?** Check whether you run cryptography (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

- cryptography (PyPI): upgrade to 3.2, 3.2.1 or later

  ```sh
  pip install "cryptography>=3.2.1"
  ```


## Affected products

- cryptography (PyPI) ECOSYSTEM:introduced=0,fixed=3.2, ECOSYSTEM:introduced=0,fixed=3.2.1

## Identifiers

- CVE-2020-25659
- GHSA-hggm-jpg3-v476
- PYSEC-2021-62

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