{"id":"UBUNTU-CVE-2026-5187","details":"Two potential heap out-of-bounds write locations existed in DecodeObjectId() in wolfcrypt/src/asn.c. First, a bounds check only validates one available slot before writing two OID arc values (out[0] and out[1]), enabling a 2-byte out-of-bounds write when outSz equals 1. Second, multiple callers pass sizeof(decOid) (64 bytes on 64-bit platforms) instead of the element count MAX_OID_SZ (32), causing the function to accept crafted OIDs with 33 or more arcs that write past the end of the allocated buffer.","modified":"2026-05-26T19:29:28.947473138Z","published":"2026-04-09T20:16:00Z","upstream":["CVE-2026-5187"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-5187"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-5187"},{"type":"REPORT","url":"https://github.com/wolfSSL/wolfssl/pull/10025"},{"type":"REPORT","url":"https://github.com/wolfSSL/wolfssl"}],"affected":[{"package":{"name":"wolfssl","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/wolfssl?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.4.8+dfsg-1"],"ecosystem_specific":{"binaries":[{"binary_name":"libcyassl5","binary_version":"3.4.8+dfsg-1"},{"binary_version":"3.4.8+dfsg-1","binary_name":"libwolfssl0"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5187.json"}},{"package":{"name":"wolfssl","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/wolfssl?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.10.2+dfsg-2","3.12.0+dfsg-1","3.12.2+dfsg-1","3.13.0+dfsg-1"],"ecosystem_specific":{"binaries":[{"binary_version":"3.13.0+dfsg-1","binary_name":"libwolfssl15"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5187.json"}},{"package":{"name":"wolfssl","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/wolfssl?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.1.0+dfsg-2","4.2.0+dfsg-1","4.2.0+dfsg-2","4.2.0+dfsg-3","4.3.0+dfsg-2"],"ecosystem_specific":{"binaries":[{"binary_name":"libwolfssl24","binary_version":"4.3.0+dfsg-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5187.json"}},{"package":{"name":"wolfssl","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/wolfssl?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.6.0-3","5.0.0-1","5.1.1-1","5.2.0-1","5.2.0-2"],"ecosystem_specific":{"binaries":[{"binary_version":"5.2.0-2","binary_name":"libwolfssl32"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5187.json"}},{"package":{"name":"wolfssl","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/wolfssl?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.5.4-2","5.5.4-2.1","5.6.4-2","5.6.6-1.2","5.6.6-1.3","5.6.6-1.3build1"],"ecosystem_specific":{"binaries":[{"binary_name":"libwolfssl42t64","binary_version":"5.6.6-1.3build1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5187.json"}},{"package":{"name":"wolfssl","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/wolfssl?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.7.2-0.1"],"ecosystem_specific":{"binaries":[{"binary_version":"5.7.2-0.1","binary_name":"libwolfssl42t64"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5187.json"}},{"package":{"name":"wolfssl","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/wolfssl?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.7.2-0.1","5.8.2-1.2","5.8.4-1","5.9.1-0.1"],"ecosystem_specific":{"binaries":[{"binary_version":"5.9.1-0.1","binary_name":"libwolfssl44"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5187.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}