What’s Vulnerable › Vulnerabilities

CVE-2017-18187

• Severity: critical (CVSS 9.8 v3.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 3.1% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2018-02-14 · updated 2026-06-17
• Weakness: CWE-190

Description

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.

Affected products

• mbedtls: before 2.7.0 — fixed in 2.7.0
• Debian Linux: 8.0, 9.0

How to fix

Upgrade to a fixed version: mbedtls 2.7.0. Check the vendor advisory for mitigations.

References

• http://www.securityfocus.com/bid/103055
• https://github.com/ARMmbed/mbedtls/blob/master/ChangeLog
• https://github.com/ARMmbed/mbedtls/commit/83c9f495ffe70c7dd280b41fdfd4881485a3bc28
• https://security.gentoo.org/glsa/201804-19
• https://usn.ubuntu.com/4267-1/
• https://www.debian.org/security/2018/dsa-4138
• https://www.debian.org/security/2018/dsa-4147
• http://www.securityfocus.com/bid/103055
• https://github.com/ARMmbed/mbedtls/blob/master/ChangeLog
• https://github.com/ARMmbed/mbedtls/commit/83c9f495ffe70c7dd280b41fdfd4881485a3bc28
• https://security.gentoo.org/glsa/201804-19
• https://usn.ubuntu.com/4267-1/

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