CVE-2016-6580 priority vulnerable to denial of service
A malicious peer can cause memory exhaustion and high CPU usage in HTTP/2 implementations using the Python priority library by assigning priority to all stream IDs.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2016-6580?
CVE-2016-6580 is a high-severity denial of service vulnerability in n/a, published on 10 Jan 2017. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A HTTP/2 implementation built using any version of the Python priority library prior to version 1.2.0 could be targeted by a malicious peer by having that peer assign priority information for every possible HTTP/2 stream ID. The priority tree would happily continue to store the priority information for each stream, and would therefore allocate unbounded amounts of memory. Attempting to actually use a tree like this would also cause extremely high CPU usage to maintain the tree.
Weakness: CWE-399
Which versions are affected by CVE-2016-6580?
3 open source packages ship an affected version, including priority. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
priority PyPI | All versions | 1.2.0 |
priority PyPI | All versions | 1.2.0 |
priority PyPI | All versions | 1.2.0 |
Products include Python Python Priority Library.
How do I fix CVE-2016-6580?
Upgrade priority to 1.2.0 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-2016-6580 being exploited?
There is no known exploitation of CVE-2016-6580 in the wild and no public exploit code.
Sources
Also known as GHSA-h3q4-6j7f-r24c, PYSEC-2017-93.