CVE-2017-3733

Encrypt-Then-Mac renegotiation crash

Description

During a renegotiation handshake if the Encrypt-Then-Mac extension is negotiated where it was not in the original handshake (or vice-versa) then this can cause OpenSSL 1.1.0 before 1.1.0e to crash (dependent on ciphersuite). Both clients and servers are affected.

Category

7.5
CVSS
Severity: High
CVSS 3.0 •
CVSS 2.0 •
EPSS 6.30% Top 10%
Vendor Advisory openssl.org
Affected: OpenSSL OpenSSL
Published at:
Updated at:

References

Link Tags
http://www.securityfocus.com/bid/96269 vdb entry third party advisory
https://www.openssl.org/news/secadv/20170216.txt vendor advisory
http://www.oracle.com/technetwork/security-advisory/cpujan2018-3236628.html
https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbgn03728en_us vdb entry third party advisory
http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html
https://github.com/openssl/openssl/commit/4ad93618d26a3ea23d36ad5498ff4f59eff3a4d2
http://www.securitytracker.com/id/1037846 vdb entry
https://www.oracle.com/technetwork/security-advisory/cpuapr2019-5072813.html

Frequently Asked Questions

What is the severity of CVE-2017-3733?
CVE-2017-3733 has been scored as a high severity vulnerability.
How to fix CVE-2017-3733?
To fix CVE-2017-3733, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2017-3733 being actively exploited in the wild?
It is possible that CVE-2017-3733 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~6% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2017-3733?
CVE-2017-3733 affects OpenSSL OpenSSL.
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