tlslite-ng up to 0.7.3 Integrity Check constanttime.py ct_check_cbc_mac_and_pad input validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.7$0-$5k0.00

A vulnerability classified as critical has been found in tlslite-ng up to 0.7.3. This affects the function ct_check_cbc_mac_and_pad of the file tlslite/utils/constanttime.py of the component Integrity Check. The manipulation with an unknown input leads to a input validation vulnerability. CWE is classifying the issue as 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. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

tlslite-ng version 0.7.3 and earlier, since commit d7b288316bca7bcdd082e6ccff5491e241305233 contains a CWE-354: Improper Validation of Integrity Check Value vulnerability in TLS implementation, tlslite/utils/constanttime.py: ct_check_cbc_mac_and_pad(); line "end_pos = data_len - 1 - mac.digest_size" that can result in an attacker manipulating the TLS ciphertext which will not be detected by receiving tlslite-ng. This attack appears to be exploitable via man in the middle on a network connection. This vulnerability appears to have been fixed after commit 3674815d1b0f7484454995e2737a352e0a6a93d8.

The bug was discovered 03/30/2018. The weakness was shared 04/18/2018 (Website). It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2018-1000159 since 04/18/2018. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability was handled as a non-public zero-day exploit for at least 19 days. During that time the estimated underground price was around $0-$5k.

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

Productinfo

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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: 5.7
VulDB Meta Temp Score: 5.7

VulDB Base Score: 5.6
VulDB Temp Score: 5.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.9
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

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

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
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Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Patch: github.com

Timelineinfo

03/30/2018 🔍
04/18/2018 +18 days 🔍
04/18/2018 +0 days 🔍
04/18/2018 +0 days 🔍
04/19/2018 +1 days 🔍
02/28/2023 +1776 days 🔍

Sourcesinfo

Advisory: github.com
Status: Not defined

CVE: CVE-2018-1000159 (🔍)

Entryinfo

Created: 04/19/2018 23:00
Updated: 02/28/2023 12:42
Changes: 04/19/2018 23:00 (58), 01/27/2020 16:13 (1), 02/28/2023 12:42 (3)
Complete: 🔍

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