CVE-2016-9243
mediumpriority · track · 31EPSS 0.035 · 89 %ileEUUSEPSS · scored 2026-10-27
HKDF in cryptography before 1.5.2 returns an empty byte-string if used with a length less than algorithm.digest_size.
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 (8)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- GHSA-q3cj-2r34-2cwcImproper input validation in cryptography2022-05-17ghsa · osvUS
HKDF in cryptography before 1.5.3 returns an empty byte-string if used with a length less than algorithm.digest_size.
- PYSEC-2017-82017-03-27vendor · osvUS
HKDF in cryptography before 1.5.2 returns an empty byte-string if used with a length less than algorithm.digest_size.
also known as (6)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (28)
External citations — patches, advisories, analysis.
- http://www.openwall.com/lists/oss-security/2016/11/09/2cnnvd
- http://www.securityfocus.com/bid/94216cnnvd
- http://www.ubuntu.com/usn/USN-3138-1cnnvd
- https://cryptography.io/en/latest/changelogcnnvd
- https://cryptography.io/en/latest/changelog/Patchcnnvd
- https://github.com/pyca/cryptography/commit/b924696b2e8731f39696584d12cceeb3aeb2d874cnnvd
- https://github.com/pyca/cryptography/issues/3211cnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/5R2ZOBMPWDFFHUZ6QOZZY36A6H5CGJXL/cnnvd
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