#37078: salted_hmac() defaults to SHA-1 algorithm despite SHA-256 being
preferred
everywhere else
-------------------------------------+-------------------------------------
Reporter: Denny Biasiolli | Type:
| Cleanup/optimization
Status: new | Component: Utilities
Version: | Severity: Normal
Keywords: security, crypto | Triage Stage:
| Unreviewed
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
The `salted_hmac()` function (`crypto.py:19`) defaults to
`algorithm="sha1"`. While HMAC-SHA1 is not cryptographically broken (HMAC
construction is resistant to collision attacks), SHA-1 is deprecated by
NIST and modern security standards recommend SHA-256 or stronger for all
new applications.
All security-sensitive callers within Django already override this default
— `Signer` uses `sha256` (signing.py:193), `PasswordResetTokenGenerator`
passes `sha256` explicitly, and session auth hashes use SHA-256. However,
any third-party code or custom application calling `salted_hmac()` without
specifying an algorithm will silently use SHA-1.
## Steps to Reproduce
1. In any Django project, call:
```python
from django.utils.crypto import salted_hmac
mac = salted_hmac("my_salt", "my_value")
print(mac.digest_size) # 20 bytes = SHA-1
```
2. Observe the HMAC uses SHA-1 without any explicit algorithm selection
## Expected Behavior
`salted_hmac()` should default to `"sha256"` to match modern cryptographic
best practices and align with Django's own internal usage.
## Actual Behavior
`salted_hmac()` defaults to `algorithm="sha1"` (line 19 of `crypto.py`).
--
Ticket URL: <https://code.djangoproject.com/ticket/37078>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.
--
You received this message because you are subscribed to the Google Groups
"Django updates" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To view this discussion visit
https://groups.google.com/d/msgid/django-updates/0107019dda2efe36-d40d0965-174d-4b7d-8fa0-4f00d444aa9d-000000%40eu-central-1.amazonses.com.
