What’s Vulnerable › Vulnerabilities
CVE-2026-5778: Integer underflow leads to out-of-bounds access in sniffer ChaCha decrypt path.
- Severity: medium (CVSS 6.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.2% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-04-09 · updated 2026-06-17
- Weakness: CWE-191
Description
Integer underflow in wolfSSL packet sniffer <= 5.9.0 allows an attacker to cause a program crash in the AEAD decryption path by injecting a TLS record shorter than the explicit IV plus authentication tag into traffic inspected by ssl_DecodePacket. The underflow wraps a 16-bit length to a large value that is passed to AEAD decryption routines, causing a large out-of-bounds read and crash. An unauthenticated attacker can trigger this remotely via malformed TLS Application Data records.
Affected products
- wolfSSL: before 5.9.1 — fixed in 5.9.1
How to fix
Upgrade to a fixed version: wolfSSL 5.9.1. Check the vendor advisory for mitigations.
References
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