CVE-2019-11873

Description

wolfSSL 4.0.0 has a Buffer Overflow in DoPreSharedKeys in tls13.c when a current identity size is greater than a client identity size. An attacker sends a crafted hello client packet over the network to a TLSv1.3 wolfSSL server. The length fields of the packet: record length, client hello length, total extensions length, PSK extension length, total identity length, and identity length contain their maximum value which is 2^16. The identity data field of the PSK extension of the packet contains the attack data, to be stored in the undefined memory (RAM) of the server. The size of the data is about 65 kB. Possibly the attacker can perform a remote code execution attack.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 6.90% Top 10%
Third-Party Advisory telekom.com Third-Party Advisory telekom.com
Affected: n/a n/a
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2019-11873?
CVE-2019-11873 has been scored as a critical severity vulnerability.
How to fix CVE-2019-11873?
To fix CVE-2019-11873, 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-2019-11873 being actively exploited in the wild?
It is possible that CVE-2019-11873 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~7% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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