CVE-2016-6580
mediumpriority · track · 31EPSS 0.018 · 78 %ileEURUUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (9)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- GHSA-h3q4-6j7f-r24cpriority vulnerable to denial of service2022-05-17ghsa · osvUS
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.
- PYSEC-2017-932017-01-10vendor · osvUS
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.
also known as (7)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (6)
External citations — patches, advisories, analysis.
- http://www.securityfocus.com/bid/92311cnnvd
- https://python-hyper.org/priority/en/latest/security/CVE-2016-6580.htmlcnnvd
- http://www.securityfocus.com/bid/92311enisa_euvd
- https://python-hyper.org/priority/en/latest/security/CVE-2016-6580.htmlenisa_euvd
- http://www.securityfocus.com/bid/92311Third Party AdvisoryVDB Entrynvd
- https://python-hyper.org/priority/en/latest/security/CVE-2016-6580.htmlMitigationVendor Advisorynvd
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