CVE-2017-18187 — In ARM mbed TLS before 2

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.

01What is this vulnerability?

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.

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2018-02-14T17:00:00.000Z
• Last modified: 2024-08-05T21:13:49.100Z

09References

• github.com — https://github.com/ARMmbed/mbedtls/commit/83c9f495ffe70c7dd280b41fdfd4881485a3bc…
• www.debian.org — https://www.debian.org/security/2018/dsa-4147
• www.debian.org — https://www.debian.org/security/2018/dsa-4138
• security.gentoo.org — https://security.gentoo.org/glsa/201804-19
• github.com — https://github.com/ARMmbed/mbedtls/blob/master/ChangeLog
• www.securityfocus.com — http://www.securityfocus.com/bid/103055
• usn.ubuntu.com — https://usn.ubuntu.com/4267-1/