cbcvebase.
CVE-2026-3547
published 2026-03-19

CVE-2026-3547: Out-of-bounds read in ALPN parsing due to incomplete validation. wolfSSL 5.8.4 and earlier contained an out-of-bounds read in ALPN handling when built with…

PriorityP337high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.26%
17.2th percentile
Out-of-bounds read in ALPN parsing due to incomplete validation. wolfSSL 5.8.4 and earlier contained an out-of-bounds read in ALPN handling when built with ALPN enabled (HAVE_ALPN / --enable-alpn). A crafted ALPN protocol list could trigger an out-of-bounds read, leading to a potential process crash (denial of service). Note that ALPN is disabled by default, but is enabled for these 3rd party compatibility features: enable-apachehttpd, enable-bind, enable-curl, enable-haproxy, enable-hitch, enable-lighty, enable-jni, enable-nginx, enable-quic.

Affected

5 ranges
VendorProductVersion rangeFixed in
debianwolfssl< wolfssl 5.9.0-0.1 (forky)wolfssl 5.9.0-0.1 (forky)
msrcazl3_mariadb_10.11.16-1_on_azure_linux_3.0
msrccbl2_mariadb_10.6.24-1_on_cbl_mariner_2.0
wolfsslwolfssl< 5.9.05.9.0
wolfsslwolfssl>= 0 < 5.9.0-0.15.9.0-0.1

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
osv7.5HIGH
vendor_debian7.5HIGH
vendor_msrc7.5HIGH
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