CVE-2019-11873
highpriority · track · 42EPSS 0.092 · 95 %ileEUUSEPSS · scored 2026-10-28
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.5–9.8
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (2)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
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references (14)
External citations — patches, advisories, analysis.
- http://www.securityfocus.com/bid/108466cnnvd
- https://github.com/wolfSSL/wolfssl/pull/2239cnnvd
- https://github.com/wolfSSL/wolfssl/pull/2239/commits/5aa5f350ba0f05a6e19e0b680a32975aa8871686cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2019-11873cnnvd
- https://wolfssl.com/wolfSSL/Home.htmlcnnvd
- https://www.securityfocus.com/bid/108466cnnvd
- https://www.telekom.com/en/corporate-responsibility/data-protection-data-security/security/details/advisories-504842cnnvd
- https://www.telekom.com/resource/blob/572524/1c89c1cbaccdf792153063b3a10af10e/dl-190515-remote-buffer-overflow-vulnerability-wolfssl-library-data.pdfcnnvd
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