CVE-2019-1547 - CVE House

Back to Database

Status published Medium CVE-2019-1547

ECDSA remote timing attack

4.7 CVSS

Vulnerability 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).

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

THREAT MONITOR

Am I Vulnerable?

Launch our assessment wizard to check if your infrastructure is exposed to • CVE-2019-1547

Check My Exposure

Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

Cesar Pereida García, Sohaib ul Hassan, Nicola Tuveri, Iaroslav Gridin, Alejandro Cabrera Aldaya, and Billy Brumley

References

More from OpenSSL

View All →

Out-of-bounds read in HTTP client no_proxy handling

Timing side-channel in SM2 algorithm on 64 bit ARM

Out-of-bounds read & write in RFC 3211 KEK Unwrap

NULL Pointer Dereference in PKCS12_item_decrypt_d2i_ex function

Missing ASN1_TYPE validation in TS_RESP_verify_response() function

Affected Vendor

OpenSSL

View all reports →

Affected Software

OpenSSL

Vulnerable Versions:

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)

Timeline

Official Publish: September 10th, 2019

Last Modified: September 16th, 2024

Added to House: July 20th, 2026

CVSS Vectors

V3: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.