Vulnerability CVE-2022-24884

Vulnerability Name:

CVE-2022-24884 (CCN-225988)

Assigned:

2022-05-05

Published:

2022-05-05

Updated:

2022-05-16

Summary:

ecdsautils is a tiny collection of programs used for ECDSA (keygen, sign, verify). `ecdsa_verify_[prepare_]legacy()` does not check whether the signature values `r` and `s` are non-zero. A signature consisting only of zeroes is always considered valid, making it trivial to forge signatures. Requiring multiple signatures from different public keys does not mitigate the issue: `ecdsa_verify_list_legacy()` will accept an arbitrary number of such forged signatures. Both the `ecdsautil verify` CLI command and the libecdsautil library are affected. The issue has been fixed in ecdsautils 0.4.1. All older versions of ecdsautils (including versions before the split into a library and a CLI utility) are vulnerable.

CVSS v3 Severity:

7.5 High (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N)
6.5 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C)

Exploitability Metrics:	Attack Vector (AV): Network Attack Complexity (AC): Low Privileges Required (PR): None User Interaction (UI): None
Scope:	Scope (S): Unchanged
Impact Metrics:	Confidentiality (C): None Integrity (I): High Availibility (A): None

5.3 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)
4.6 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:U/RL:O/RC:C)

Exploitability Metrics:	Attack Vector (AV): Network Attack Complexity (AC): Low Privileges Required (PR): None User Interaction (UI): None
Scope:	Scope (S): Unchanged
Impact Metrics:	Confidentiality (C): None Integrity (I): Low Availibility (A): None

CVSS v2 Severity:

5.0 Medium (CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:P/A:N)

Exploitability Metrics:	Access Vector (AV): Network Access Complexity (AC): Low Authentication (Au): None
Impact Metrics:	Confidentiality (C): None Integrity (I): Partial Availibility (A): None

5.0 Medium (CCN CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:P/A:N)

Exploitability Metrics:	Access Vector (AV): Network Access Complexity (AC): Low Athentication (Au): None
Impact Metrics:	Confidentiality (C): None Integrity (I): Partial Availibility (A): None