CVE-2022-42966 Exponential ReDoS in cleo leads to denial of service
An attacker can cause a denial of service in the cleo Python library by supplying malicious input to the Table.set_rows method, triggering exponential regex backtracking.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2022-42966?
CVE-2022-42966 is a medium-severity denial of service vulnerability in cleo, published on 9 Nov 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
An exponential ReDoS (Regular Expression Denial of Service) can be triggered in the cleo PyPI package, when an attacker is able to supply arbitrary input to the Table.set_rows method
Weakness: CWE-1333
Which versions are affected by CVE-2022-42966?
3 open source packages ship an affected version, including cleo. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
cleo PyPI | All versions | 2.0.0 |
cleo PyPI | From 1.0.0a1 | 2.0.0 |
cleo PyPI | From 1.0.0a1 | 2.0.0 |
Products include Python-Poetry Cleo.
How do I fix CVE-2022-42966?
Upgrade cleo to 2.0.0 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2022-42966 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2022-42966 exists.
Sources
Also known as GHSA-2p9h-ccw7-33gf, PYSEC-2022-43178, UBUNTU-CVE-2022-42966.