CVE-2019-11873
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (9.25%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 9.25% probability · 95th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-787
- Affected
- wolfssl/wolfssl
- Source
- cve@mitre.org
EPSS 9.2% since 27 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://www.securityfocus.com/bid/108466Broken Link
- https://www.telekom.com/en/corporate-responsibility/data-protection-data-security/security/details/advisories-504842Third Party Advisory
- https://www.telekom.com/resource/blob/572524/1c89c1cbaccdf792153063b3a10af10e/dl-190515-remote-buffer-overflow-vulnerability-wolfssl-library-data.pdfPatch, Third Party Advisory
- http://www.securityfocus.com/bid/108466Broken Link
- https://www.telekom.com/en/corporate-responsibility/data-protection-data-security/security/details/advisories-504842Third Party Advisory
- https://www.telekom.com/resource/blob/572524/1c89c1cbaccdf792153063b3a10af10e/dl-190515-remote-buffer-overflow-vulnerability-wolfssl-library-data.pdfPatch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.