CVE-2019-1547

Advisory lineage Upstream: 0 Downstream: 28
Modified
Published: 10 Sept 2019, 16:58
Last modified:16 Sept 2024, 16:33

Vulnerability Summary

Overall Risk (default)
low
19/100
CVSS Score
4.7 MEDIUM
v3.1 (nvd)
EPSS Score
0.26% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

10 Sept 2019, 16:58
Published
Vulnerability first disclosed
16 Sept 2024, 16:33
Last Modified
Vulnerability information updated

Description

Normally in OpenSSL EC groups always have a co-factor present and this is used in side channel resistant code paths. However, in some cases, it is possible to construct a group using explicit parameters (instead of using a named curve). In those cases it is possible that such a group does not have the cofactor present. This can occur even where all the parameters match a known named curve. If such a curve is used then OpenSSL falls back to non-side channel resistant code paths which may result in full key recovery during an ECDSA signature operation. In order to be vulnerable an attacker would have to have the ability to time the creation of a large number of signatures where explicit parameters with no co-factor present are in use by an application using libcrypto. For the avoidance of doubt libssl is not vulnerable because explicit parameters are never used. Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c). Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k). Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s).

CVSS Metrics

  • v3.1•MEDIUM•Score: 4.7CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
  • v2.0•LOW•Score: 1.9AV:L/AC:M/Au:N/C:P/I:N/A:N

EPSS Trends

Current EPSS score: 0.26%• Percentile: 50%

Affected Systems

  • Unknown•OpenSSL

    ≥ 1.0.2, ≤ 1.0.2s | ≥ 1.1.0, ≤ 1.1.0k | ≥ 1.1.1, ≤ 1.1.1c | Fixed in OpenSSL 1.1.1d (Affected 1.1.1-1.1.1c) | Fixed in OpenSSL 1.1.0l (Affected 1.1.0-1.1.0k) | Fixed in OpenSSL 1.0.2t (Affected 1.0.2-1.0.2s)

References (35)