CVE-2026-5778

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/wolfSSL/wolfssl/pull/10125	Issue Tracking Patch

Configurations

Configuration 1 (hide)

cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*

History

29 Apr 2026, 14:50

Type	Values Removed	Values Added
First Time		Wolfssl Wolfssl wolfssl
CPE		cpe:2.3:a:wolfssl:wolfssl::::::::
References	~~() https://github.com/wolfSSL/wolfssl/pull/10125 -~~	() https://github.com/wolfSSL/wolfssl/pull/10125 - Issue Tracking, Patch
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 6.5

09 Apr 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-09 22:16

Updated : 2026-04-29 14:50

NVD link : CVE-2026-5778

Mitre link : CVE-2026-5778

CVE.ORG link : CVE-2026-5778

JSON object : View

Products Affected

wolfssl

wolfssl

CWE

CWE-191

Integer Underflow (Wrap or Wraparound)

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