CVE-2026-2646: A heap-buffer-overflow vulnerability exists in wolfSSL's wolfSSL_d2i_SSL_SESSION() function. When deserializing session data with SESSION_CERTS enabled…

PriorityP346high8.1CVSS 3.1

AVNACHPRNUINSUCHIHAH

EPSS

0.12%

2.5th percentile

A heap-buffer-overflow vulnerability exists in wolfSSL's wolfSSL_d2i_SSL_SESSION() function. When deserializing session data with SESSION_CERTS enabled, certificate and session id lengths are read from an untrusted input without bounds validation, allowing an attacker to overflow fixed-size buffers and corrupt heap memory. A maliciously crafted session would need to be loaded from an external source to trigger this vulnerability. Internal sessions were not vulnerable.

Affected

6 ranges

Vendor	Product	Version range	Fixed in
debian	wolfssl	< wolfssl 5.9.0-0.1 (forky)	wolfssl 5.9.0-0.1 (forky)
msrc	azl3_mariadb_10.11.16-1_on_azure_linux_3.0	—	—
msrc	cbl2_mariadb_10.6.24-1_on_cbl_mariner_2.0	—	—
wolfssl	wolfssl	< 5.9.0	5.9.0
wolfssl	wolfssl	<= 5.8.4	—
wolfssl	wolfssl	>= 0 < 5.9.0-0.1	5.9.0-0.1

CVSS provenance

nvdv3.18.1HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

nvdv4.05.0MEDIUMCVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:L/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

osv5.0MEDIUM

vendor_debian5.0MEDIUM

vendor_msrc5.0MEDIUM

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