Medium
Security advisory
A Lucky 13 timing side channel in mbedtls_ssl_decrypt_buf in library/ssl_msg.c in Trusted Firmware Mbed TLS through 2.23.0 allows an attacker to recover secret key information. This affects CBC mode because of a computed time difference based on a padding length.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2020-16150
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 04:54 UTC · Revision 1
Source evidence
A Lucky 13 timing side channel in mbedtls_ssl_decrypt_buf in library/ssl_msg.c in Trusted Firmware Mbed TLS through 2.23.0 allows an attacker to recover secret key information. This affects CBC mode because of a computed time difference based on a padding length.
osv:CVE-2020-16150
Complete source record
{
"id": "349533e1e662785b6c9dd65701a2d924918b536a0e86a61b6921b4a387196007",
"url": "https://osv.dev/vulnerability/CVE-2020-16150",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "CVE-2020-16150",
"summary": "A Lucky 13 timing side channel in mbedtls_ssl_decrypt_buf in library/ssl_msg.c in Trusted Firmware Mbed TLS through 2.23.0 allows an attacker to recover secret key information. This affects CBC mode because of a computed time difference based on a padding length.",
"evidence": "osv:CVE-2020-16150",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2020-16150",
"aliases": [
"CVE-2020-16150"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/Mbed-TLS/mbedtls",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "7cd4d2dadb5fdc8410ee667f062646bd28f37e62"
},
{
"introduced": "8be0e6db41b4a085e90cb03983f99d3a5158d450"
},
{
"fixed": "848a4e06b375e067552f1a21d4bc69322c673217"
},
{
"introduced": "3f8d78411a26e833db18d9fbde0e2f0baeda87f0"
},
{
"fixed": "523f0554b6cdc7ace5d360885c3f5bbcc73ec0e8"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:arm:mbed_tls:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "2.7.17"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:arm:mbed_tls:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "2.8.0"
},
{
"fixed": "2.16.8"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:arm:mbed_tls:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "2.17.0"
},
{
"fixed": "2.24.0"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"mbedtls-2.19.1",
"mbedtls-2.7.15",
"mbedtls-2.16.6",
"mbedtls-2.22.0d0",
"mbedtls-2.7.14",
"mbedtls-2.16.5",
"mbedtls-2.21.0",
"mbedtls-2.7.13",
"mbedtls-2.20.0",
"mbedtls-2.16.4",
"mbedtls-2.20.0d0",
"mbedtls-2.16.3",
"mbedtls-2.7.12",
"mbedtls-2.19.0d2",
"mbedtls-2.19.0",
"mbedtls-2.19.0d1",
"mbedtls-2.16.2",
"mbedtls-2.7.11",
"mbedtls-2.7.9",
"mbedtls-2.16.0",
"mbedtls-2.14.0",
"mbedtls-2.7.8",
"mbedtls-2.7.7",
"mbedtls-2.13.1",
"mbedtls-2.13.0",
"mbedtls-2.7.6",
"mbedtls-2.12.0",
"mbedtls-2.7.5",
"mbedtls-2.11.0",
"mbedtls-2.7.4",
"mbedtls-2.10.0",
"mbedtls-2.7.0",
"mbedtls-2.7.3",
"mbedtls-2.9.0",
"mbedtls-2.7.2",
"mbedtls-2.8.0",
"mbedtls-2.7.2-rc1",
"mbedtls-2.7.1",
"mbedtls-2.7.0-rc1",
"mbedtls-2.6.0",
"mbedtls-2.6.0-rc1",
"mbedtls-2.5.1",
"mbedtls-2.5.0",
"mbedtls-2.4.0",
"mbedtls-2.2.1",
"yotta-2.3.1",
"mbedtls-2.3.0",
"mbedtls-2.2.0",
"mbedos-release-15-11",
"mbedos-techcon-oob2",
"mbedtls-2.1.2",
"mbedtls-2.1.0",
"mbedtls-2.1.1",
"beta-oob-2",
"mbedtls-2.0.0",
"polarssl-1.3.9",
"polarssl-1.3.8",
"polarssl-1.3.7",
"polarssl-1.3.6",
"polarssl-1.3.5",
"polarssl-1.3.4",
"polarssl-1.3.3",
"polarssl-1.3.2",
"polarssl-1.3.1",
"polarssl-1.3.0",
"polarssl-1.3.0-rc0",
"polarssl-1.2.6",
"polarssl-1.2.5",
"polarssl-1.2.4",
"polarssl-1.2.2",
"polarssl-1.2.1",
"polarssl-1.2.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-16150.json"
}
}
],
"modified": "2026-10-24T10:30:22.834921339Z",
"provider": "osv",
"references": [
"https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html",
"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5OSOFUD6UTGTDDSQRS62BPXDU52I6PUA/",
"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IRPBHCQKZXHVKOP5O5EWE7P76AWGUXQJ/",
"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OD3NM6GD73CTFFRBKG5G2ACXGG7QQHCC/",
"https://tls.mbed.org/tech-updates/security-advisories",
"https://tls.mbed.org/tech-updates/security-advisories/mbedtls-security-advisory-2020-09-1"
],
"provider_metadata": {
"unresolved_ranges": [
{
"cpes": [
"cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*"
],
"vendor_product": "debian:debian_linux",
"extracted_events": [
{
"range": [
{
"introduced": "10.0"
},
{
"last_affected": "10.0"
}
],
"source": "CPE_STRING"
}
]
},
{
"cpes": [
"cpe:2.3:o:fedoraproject:fedora:31:*:*:*:*:*:*:*",
"cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*",
"cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*"
],
"vendor_product": "fedoraproject:fedora",
"extracted_events": [
{
"range": [
{
"introduced": "31"
},
{
"last_affected": "31"
},
{
"introduced": "32"
},
{
"last_affected": "32"
},
{
"introduced": "33"
},
{
"last_affected": "33"
}
],
"source": "CPE_STRING"
}
]
}
]
}
},
"related_cves": [
{
"value": "CVE-2020-16150",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 430778,
"published_at": "2020-09-02T16:15:12.363+00:00"
}