[Security] Bump rsa from 4.0 to 4.7.2

[dependabot-preview]

Bumps rsa from 4.0 to 4.7.2.

Changelog

Sourced from rsa's changelog.

Version 4.7.2 - released 2021-02-24

• Fix picking/unpickling issue introduced in 4.7 (#173)

Version 4.7.1 - released 2021-02-15

• Fix threading issue introduced in 4.7 (#173)

Version 4.7 - released 2021-01-10

• Fix #165: CVE-2020-25658 - Bleichenbacher-style timing oracle in PKCS#1 v1.5 decryption code
• Add padding length check as described by PKCS#1 v1.5 (Fixes #164)
• Reuse of blinding factors to speed up blinding operations. Fixes #162.
• Declare & test support for Python 3.9

Version 4.4 & 4.6 - released 2020-06-12

Version 4.4 and 4.6 are almost a re-tagged release of version 4.2. It requires Python 3.5+. To avoid older Python installations from trying to upgrade to RSA 4.4, this is now made explicit in the python_requires argument in setup.py. There was a mistake releasing 4.4 as "3.5+ only", which made it necessary to retag 4.4 as 4.6 as well.

No functional changes compared to version 4.2.

Version 4.3 & 4.5 - released 2020-06-12

Version 4.3 and 4.5 are almost a re-tagged release of version 4.0. It is the last to support Python 2.7. This is now made explicit in the python_requires argument in setup.py. Python 3.4 is not supported by this release. There was a mistake releasing 4.4 as "3.5+ only", which made it necessary to retag 4.3 as 4.5 as well.

Two security fixes have also been backported, so 4.3 = 4.0 + these two fixes.

• Choose blinding factor relatively prime to N. Thanks Christian Heimes for pointing this out.
• Reject cyphertexts (when decrypting) and signatures (when verifying) that have been modified by prepending zero bytes. This resolves CVE-2020-13757. Thanks Carnil for pointing this out.

Version 4.2 - released 2020-06-10

... (truncated)

Commits

• 8766407 Bumped version to 4.7.2
• 130eb4e Add pickling fix to CHANGELOG
• eb6ddb6 Fix #173: unpickling doesn't restore full object
• 758562f Mark version 4.7.1 as released
• 63488be Bumped version to 4.7.1
• 88418f0 Fix threading issue introduced in 4.7
• 3af4e65 Fix link formatting in CHANGELOG
• 7508737 Bumped version to 4.7.1-dev0
• fa3282a Bumped version to 4.7
• a364e82 Marked version 4.7 as released
• Additional commits viewable in compare view

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[dependabot-preview]

We've just been alerted that this update fixes a security vulnerability:

Sourced from The GitHub Security Advisory Database.

Access Restriction Bypass

Python-RSA 4.0 ignores leading '\0' bytes during decryption of ciphertext. This could conceivably have a security-relevant impact, e.g., by helping an attacker to infer that an application uses Python-RSA, or if the length of accepted ciphertext affects application behavior (such as by causing excessive memory allocation).

Affected versions: ["< 4.1"]