cryptsetup 2.2.0 LUKS2 Validator luks2_json_metadata.c hdr_validate_segments out-of-bounds write

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.5$0-$5k0.00

A vulnerability, which was classified as critical, has been found in cryptsetup 2.2.0. Affected by this issue is the function hdr_validate_segments in the library lib/luks2/luks2_json_metadata.c of the component LUKS2 Validator. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. Using CWE to declare the problem leads to CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. CVE summarizes:

A vulnerability was found in upstream release cryptsetup-2.2.0 where, there's a bug in LUKS2 format validation code, that is effectively invoked on every device/image presenting itself as LUKS2 container. The bug is in segments validation code in file 'lib/luks2/luks2_json_metadata.c' in function hdr_validate_segments(struct crypt_device *cd, json_object *hdr_jobj) where the code does not check for possible overflow on memory allocation used for intervals array (see statement "intervals = malloc(first_backup * sizeof(*intervals));"). Due to the bug, library can be *tricked* to expect such allocation was successful but for far less memory then originally expected. Later it may read data FROM image crafted by an attacker and actually write such data BEYOND allocated memory.

The weakness was published 09/16/2020 as Bug 1874712 as not defined bug report (Bugzilla). The advisory is shared for download at bugzilla.redhat.com. This vulnerability is handled as CVE-2020-14382 since 06/17/2020. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.5

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
unlockunlockunlockunlockunlockunlock
unlockunlockunlockunlockunlockunlock
unlockunlockunlockunlockunlockunlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Dayunlockunlockunlockunlock
Todayunlockunlockunlockunlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

06/17/2020 🔍
09/16/2020 +91 days 🔍
09/16/2020 +0 days 🔍
09/16/2020 +0 days 🔍

Sourcesinfo

Advisory: Bug 1874712
Status: Not defined

CVE: CVE-2020-14382 (🔍)

Entryinfo

Created: 09/16/2020 21:11
Updated: 09/16/2020 21:16
Changes: 09/16/2020 21:11 (40), 09/16/2020 21:16 (17)
Complete: 🔍

Discussion

No comments yet. Languages: en.

Please log in to comment.

Do you know our Splunk app?

Download it now for free!