LibTomCrypt prior 2.2.0 rsa_verify_hash.c rsa_verify_hash_ex Signature input validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.2$0-$5k0.00

Summaryinfo

A vulnerability was found in LibTomCrypt and classified as critical. Affected by this issue is the function rsa_verify_hash_ex of the file rsa_verify_hash.c. Executing a manipulation can lead to input validation (Signature). This vulnerability is handled as CVE-2016-6129. The attack can be executed remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in LibTomCrypt. It has been declared as critical. This vulnerability affects the function rsa_verify_hash_ex of the file rsa_verify_hash.c. The manipulation with an unknown input leads to a input validation vulnerability (Signature). 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 confidentiality, integrity, and availability. CVE summarizes:

The rsa_verify_hash_ex function in rsa_verify_hash.c in LibTomCrypt, as used in OP-TEE before 2.2.0, does not validate that the message length is equal to the ASN.1 encoded data length, which makes it easier for remote attackers to forge RSA signatures or public certificates by leveraging a Bleichenbacher signature forgery attack.

The bug was discovered 08/28/2016. The weakness was released 02/13/2017 as Bug 1370955 as not defined bug report (Bugzilla). The advisory is shared for download at bugzilla.redhat.com. This vulnerability was named CVE-2016-6129 since 06/30/2016. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 9 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 93353 (Debian DLA-612-1 : libtomcrypt security update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Debian Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 351052 (Amazon Linux Security Advisory for libtommath,libtomcrypt: ALAS-2017-864).

Upgrading to version 2.2.0 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 vulnerability database at Tenable (93353). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • OP-TEE

Productinfo

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.4
VulDB Meta Temp Score: 7.2

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Name: Signature
Class: Input validation / Signature
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: 93353
Nessus Name: Debian DLA-612-1 : libtomcrypt security update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: LibTomCrypt 2.2.0
Patch: github.com

Timelineinfo

06/30/2016 🔍
08/28/2016 +59 days 🔍
09/06/2016 +9 days 🔍
09/08/2016 +2 days 🔍
02/13/2017 +158 days 🔍
02/13/2017 +0 days 🔍
02/14/2017 +1 days 🔍
11/14/2022 +2099 days 🔍

Sourcesinfo

Advisory: Bug 1370955
Status: Not defined
Confirmation: 🔍

CVE: CVE-2016-6129 (🔍)
GCVE (CVE): GCVE-0-2016-6129
GCVE (VulDB): GCVE-100-96856
OSVDB: - CVE-2016-6129 - OP-TEE - Bleichenbacher Signature Forgery Issue

Entryinfo

Created: 02/14/2017 09:07
Updated: 11/14/2022 08:32
Changes: 02/14/2017 09:07 (70), 09/01/2020 20:29 (5), 11/14/2022 08:32 (4)
Complete: 🔍
Cache ID: 216::103

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