CVE-2022-23651 b2-sdk-python TOCTOU application key disclosure
Local attackers can exploit a race condition to read sensitive API keys from the SDK's SQLite account info file during creation.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2022-23651?
CVE-2022-23651 is a medium-severity vulnerability in Backblaze b2-sdk-python, published on 23 Feb 2022. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
b2-sdk-python is a python library to access cloud storage provided by backblaze. Linux and Mac releases of the SDK version 1.14.0 and below contain a key disclosure vulnerability that, in certain conditions, can be exploited by local attackers through a time-of-check-time-of-use (TOCTOU) race condition. SDK users of the SqliteAccountInfo format are vulnerable while users of the InMemoryAccountInfo format are safe. The SqliteAccountInfo saves API keys (and bucket name-to-id mapping) in a local database file ($XDG_CONFIG_HOME/b2/account_info, ~/.b2_account_info or a user-defined path). When first created, the file is world readable and is (typically a few milliseconds) later altered to be private to the user. If the directory containing the file is readable by a local attacker then during the brief period between file creation and permission modification, a local attacker can race to open the file and maintain a handle to it. This allows the local attacker to read the contents after the file after the sensitive information has been saved to it. Consumers of this SDK who rely on it to save data using SqliteAccountInfo class should upgrade to the latest version of the SDK. Those who believe a local user might have opened a handle using this race condition, should remove the affected database files and regenerate all application keys. Users should upgrade to b2-sdk-python 1.14.1 or later.
Weakness: CWE-367
Which versions are affected by CVE-2022-23651?
3 open source packages ship an affected version, including b2sdk. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
b2sdk PyPI | All versions | 1.14.1 |
b2sdk PyPI | All versions | 1.14.1 |
b2sdk PyPI | All versions | 1.14.1 |
Products include Backblaze B2 Python Software Development Kit.
How do I fix CVE-2022-23651?
Upgrade b2sdk to 1.14.1 or later.
Is CVE-2022-23651 being exploited?
There is no known exploitation of CVE-2022-23651 in the wild and no public exploit code.
Sources
Also known as GHSA-p867-fxfr-ph2w, PYSEC-2022-33.