VDB-113268 · CVE-2017-18187 · BID 103055

ARM mbed TLS up to 2.6.x PSK Identity library/ssl_srv.c ssl_parse_client_psk_identity integer overflow

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability, which was classified as critical, was found in ARM mbed TLS up to 2.6.x. Affected is the function ssl_parse_client_psk_identity of the file library/ssl_srv.c of the component PSK Identity Handler. The manipulation with an unknown input leads to a integer overflow vulnerability. CWE is classifying the issue as CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In ARM mbed TLS before 2.7.0, there is a bounds-check bypass through an integer overflow in PSK identity parsing in the ssl_parse_client_psk_identity() function in library/ssl_srv.c.

The bug was discovered 06/26/2017. The weakness was presented 02/14/2018 (GitHub Repository). The advisory is shared for download at github.com. This vulnerability is traded as CVE-2017-18187 since 02/14/2018. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 233 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 106918 (openSUSE Security Update : mbedtls (openSUSE-2018-186)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family SuSE Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 176329 (Debian Security Update for polarssl (DSA 4147-1)).

Upgrading to version 2.7.0 eliminates this vulnerability. A possible mitigation has been published 6 days after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (106918). See 113192 and 113193 for similar entries.





CPE 2.3info

CPE 2.2info


VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
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VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.1

VulDB Base Score: 7.3
VulDB Temp Score: 6.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍



VulDB Base Score: 🔍
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Class: Integer overflow
CWE: CWE-190 / CWE-189
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

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EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍


Nessus ID: 106918
Nessus Name: openSUSE Security Update : mbedtls (openSUSE-2018-186)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 65722
OpenVAS Name: Debian Security Advisory DSA 4147-1 (polarssl - security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: ARM mbed TLS 2.7.0
Patch: github.com


06/26/2017 🔍
02/14/2018 +233 days 🔍
02/14/2018 +0 days 🔍
02/14/2018 +0 days 🔍
02/14/2018 +0 days 🔍
02/15/2018 +1 days 🔍
02/20/2018 +5 days 🔍
02/21/2018 +1 days 🔍
02/06/2023 +1811 days 🔍


Advisory: 83c9f495ffe70c7dd280b41fdfd4881485a3bc28
Status: Not defined
Confirmation: 🔍

CVE: CVE-2017-18187 (🔍)

SecurityFocus: 103055 - ARM mbed TLS CVE-2017-18187 Integer Overflow Vulnerability

See also: 🔍


Created: 02/15/2018 08:34 AM
Updated: 02/06/2023 04:07 PM
Changes: 02/15/2018 08:34 AM (78), 01/04/2020 08:03 PM (5), 02/06/2023 04:01 PM (5), 02/06/2023 04:07 PM (1)
Complete: 🔍


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