Headline
Ubuntu Security Notice USN-6239-1
Ubuntu Security Notice 6239-1 - It was discovered that ECDSA Util did not properly verify certain signature values. An attacker could possibly use this issue to bypass signature verification.
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Ubuntu Security Notice USN-6239-1
July 20, 2023
ecdsautils vulnerability
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 22.04 LTS
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS (Available with Ubuntu Pro)
- Ubuntu 16.04 LTS (Available with Ubuntu Pro)
Summary:
ECDSA Util could be made to accept forged signatures.
Software Description:
- ecdsautils: ECDSA elliptic curve cryptography command line tools
Details:
It was discovered that ECDSA Util did not properly verify certain
signature values.
An attacker could possibly use this issue to bypass signature
verification.
Update instructions:
The problem can be corrected by updating your system to the following
package versions:
Ubuntu 22.04 LTS:
ecdsautils 0.3.2+git20151018-2+deb10u1build0.22.04.1
Ubuntu 20.04 LTS:
ecdsautils 0.3.2+git20151018-2+deb10u1build0.20.04.1
Ubuntu 18.04 LTS (Available with Ubuntu Pro):
ecdsautils 0.3.2+git20151018-2ubuntu0.18.04.1~esm1
Ubuntu 16.04 LTS (Available with Ubuntu Pro):
ecdsautils 0.3.2+git20151018-2ubuntu0.16.04.1~esm1
In general, a standard system update will make all the necessary changes.
References:
https://ubuntu.com/security/notices/USN-6239-1
CVE-2022-24884
Package Information:
https://launchpad.net/ubuntu/+source/ecdsautils/0.3.2+git20151018-2+deb10u1build0.22.04.1
https://launchpad.net/ubuntu/+source/ecdsautils/0.3.2+git20151018-2+deb10u1build0.20.04.1
Related news
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.