cryptography up to 1.5.1 HKDF input validation

CVSS Meta Temp Score
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CTI Interest Score
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7.3$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in cryptography up to 1.5.1. This impacts an unknown function of the component HKDF. This manipulation causes input validation. This vulnerability is registered as CVE-2016-9243. Remote exploitation of the attack is possible. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in cryptography up to 1.5.1. Affected by this vulnerability is some unknown processing of the component HKDF. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect integrity. The summary by CVE is:

HKDF in cryptography before 1.5.2 returns an empty byte-string if used with a length less than algorithm.digest_size.

The bug was discovered 11/24/2016. The weakness was published 03/27/2017 by Markus Döring (oss-sec). The advisory is shared at openwall.com. This vulnerability is known as CVE-2016-9243 since 11/09/2016. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 94994 (Fedora 25 : python-cryptography / python-cryptography-vectors (2016-2d90e27e50)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Fedora Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 196635 (Ubuntu Security Notification for Python-cryptography Vulnerability (USN-3138-1)).

Upgrading to version 1.5.2 eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (94994) and SecurityFocus (BID 94216†). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

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Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.3

VulDB Base Score: 7.5
VulDB Temp Score: 7.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
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NVD Base Score: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 94994
Nessus Name: Fedora 25 : python-cryptography / python-cryptography-vectors (2016-2d90e27e50)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 831735
OpenVAS Name: Fedora Update for python-cryptography FEDORA-2016-d3a2b640ce
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: cryptography 1.5.2
Patch: github.com

Timelineinfo

11/08/2016 🔍
11/09/2016 +1 days 🔍
11/19/2016 +10 days 🔍
11/21/2016 +2 days 🔍
11/24/2016 +3 days 🔍
03/27/2017 +123 days 🔍
03/27/2017 +0 days 🔍
03/28/2017 +1 days 🔍
09/17/2024 +2730 days 🔍

Sourcesinfo

Advisory: FEDORA-2016-2d90e27e50
Researcher: Markus Döring
Status: Not defined
Confirmation: 🔍

CVE: CVE-2016-9243 (🔍)
GCVE (CVE): GCVE-0-2016-9243
GCVE (VulDB): GCVE-100-98965
SecurityFocus: 94216 - Python Cryptography CVE-2016-9243 Security Bypass Vulnerability
OSVDB: - CVE-2016-9243 - HKDF - Security Bypass Issue

Entryinfo

Created: 03/28/2017 22:13
Updated: 09/17/2024 11:12
Changes: 03/28/2017 22:13 (73), 08/23/2020 11:46 (3), 11/22/2022 15:23 (5), 11/22/2022 15:29 (1), 09/09/2024 16:00 (15), 09/17/2024 11:12 (2)
Complete: 🔍
Cache ID: 216::103

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