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Fencer Intel
medium 5.5

CVE-2020-16150 json

A Lucky 13 timing side channel in `mbedtls_ssl_decrypt_buf` in `library/ssl_msg.c` in Trusted...

published 6y ago modified 3mo ago also EUVD-2020-8116 , JLSEC-2025-202

cvss
5.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 32%
public exploits
0
none known

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.

Patch / fix

  • julia MbedTLS_jll 2.16.8+0
  • arm mbed_tls 2.7.17, 2.16.8, 2.24.0
  • mbedtls Debian 14, Debian 13, Debian 12 2.16.9-0.1

debian advisories DEBIAN-CVE-2020-16150

  • mbedtls Alpine 3.24, Alpine 3.23, Alpine 3.22 +12 more 2.16.8-r0
  • mbedtls2 Alpine 3.24, Alpine 3.23, Alpine 3.22 +2 more 2.16.8-r0
  • mbedtls3 Alpine 3.24 2.16.8-r0

alpine advisories ALPINE-CVE-2020-16150

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • mbedtls Arch Linux 2.25.0-1

arch linux advisories AVG-1386

Is CVE-2020-16150 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2020-16150 updated cvss 4.7

mbedtls: local side channel attack on classical CBC decryption in (D)TLS

  • Red Hat All currently supported Red Hat products
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.38% chance of exploitation in the next 30 days, higher than 32% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
NVD 2.0 2.1 AV:L/AC:L/Au:N/C:P/I:N/A:N
OSV 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Affected packages

ecosystem package affected fixed in
julia MbedTLS_jll
<2.16.8+0
2.16.8+0

Classification

Weakness

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.