CVE-2016-9243

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Summary

CVECVE-2016-9243
StatePUBLISHED
Assignerredhat
Source PriorityCVE Program / NVD first with legacy fallback
Published2017-03-27 17:59:00 UTC
Updated2025-04-20 01:37:25 UTC
DescriptionHKDF in cryptography before 1.5.2 returns an empty byte-string if used with a length less than algorithm.digest_size.

Risk And Classification

Primary CVSS: v3.1 7.5 HIGH from [email protected]

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Problem Types: NVD-CWE-noinfo | n/a

VersionSourceTypeScoreSeverityVector
3.1[email protected]Primary7.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
2.0[email protected]Primary5AV:N/AC:L/Au:N/C:N/I:P/A:N

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS v2.0 Breakdown

Access Vector
Network
Access Complexity
Low
Authentication
None
Confidentiality
None
Integrity
Partial
Availability
None

AV:N/AC:L/Au:N/C:N/I:P/A:N

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Operating System Canonical Ubuntu Linux 16.04 All All All
Operating System Canonical Ubuntu Linux 16.10 All All All
Application Cryptography.io Cryptography All All All All
Operating System Fedoraproject Fedora 23 All All All
Operating System Fedoraproject Fedora 24 All All All
Operating System Fedoraproject Fedora 25 All All All

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Na N/a affected n/a Not specified

References

ReferenceSourceLinkTags
USN-3138-1: python-cryptography vulnerability | Ubuntu af854a3a-2127-422b-91ae-364da2661108 www.ubuntu.com Third Party Advisory
Python Cryptography CVE-2016-9243 Security Bypass Vulnerability af854a3a-2127-422b-91ae-364da2661108 www.securityfocus.com Broken Link, Third Party Advisory, VDB Entry
HKDF key-length inconsistency · Issue #3211 · pyca/cryptography · GitHub af854a3a-2127-422b-91ae-364da2661108 github.com Issue Tracking, Third Party Advisory
oss-security - Re: CVE Request: Cryptography 1.5.3: HKDF might return an empty byte-string af854a3a-2127-422b-91ae-364da2661108 www.openwall.com Mailing List, Patch, VDB Entry
[SECURITY] Fedora 24 Update: python-cryptography-1.5.3-3.fc24 - package-announce - Fedora Mailing-Lists af854a3a-2127-422b-91ae-364da2661108 lists.fedoraproject.org Mailing List, Third Party Advisory
Changelog — Cryptography 2.1.dev1 documentation af854a3a-2127-422b-91ae-364da2661108 cryptography.io Release Notes, Third Party Advisory
[SECURITY] Fedora 23 Update: python-cryptography-vectors-1.5.3-1.fc23 - package-announce - Fedora Mailing-Lists af854a3a-2127-422b-91ae-364da2661108 lists.fedoraproject.org Mailing List, Third Party Advisory
Fixes #3211 -- fixed hkdf's output with short length (#3215) · pyca/cryptography@b924696 · GitHub af854a3a-2127-422b-91ae-364da2661108 github.com Patch, Third Party Advisory
[SECURITY] Fedora 25 Update: python-cryptography-vectors-1.5.3-1.fc25 - package-announce - Fedora Mailing-Lists af854a3a-2127-422b-91ae-364da2661108 lists.fedoraproject.org Mailing List, Third Party Advisory
[SECURITY] Fedora 25 Update: python-cryptography-vectors-1.5.3-1.fc25 - package-announce - Fedora Mailing-Lists MITRE lists.fedoraproject.org
[SECURITY] Fedora 24 Update: python-cryptography-1.5.3-3.fc24 - package-announce - Fedora Mailing-Lists MITRE lists.fedoraproject.org
[SECURITY] Fedora 23 Update: python-cryptography-vectors-1.5.3-1.fc23 - package-announce - Fedora Mailing-Lists MITRE lists.fedoraproject.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 670239 EulerOS Security Update for python-cryptography (EulerOS-SA-2021-1837)
  • 670669 EulerOS Security Update for python-cryptography (EulerOS-SA-2021-2428)

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