IO FinNet tss-lib up to 1.x Modular Exponentiation paillier.go timing discrepancy

CVSS Meta Temp Score
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CTI Interest Score
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5.0$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in IO FinNet tss-lib up to 1.x. The affected element is an unknown function of the file crypto/paillier/paillier.go of the component Modular Exponentiation Handler. This manipulation causes timing discrepancy. This vulnerability is registered as CVE-2023-26557. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic was found in IO FinNet tss-lib up to 1.x. Affected by this vulnerability is an unknown code of the file crypto/paillier/paillier.go of the component Modular Exponentiation Handler. The manipulation with an unknown input leads to a timing discrepancy vulnerability. The CWE definition for the vulnerability is CWE-208. Two separate operations in a product require different amounts of time to complete, in a way that is observable to an actor and reveals security-relevant information about the state of the product, such as whether a particular operation was successful or not. As an impact it is known to affect confidentiality. The summary by CVE is:

io.finnet tss-lib before 2.0.0 can leak the lambda value of a private key via a timing side-channel attack because it relies on Go big.Int, which is not constant time for Cmp, modular exponentiation, or modular inverse. An example leak is in crypto/paillier/paillier.go. (bnb-chain/tss-lib and thorchain/tss are also affected.)

The weakness was published 04/21/2023. It is possible to read the advisory at github.com. This vulnerability is known as CVE-2023-26557 since 02/26/2023. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1592 according to MITRE ATT&CK.

Upgrading to version 2.0.0 eliminates this vulnerability. The upgrade is hosted for download at github.com.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2023-1438). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.0
VulDB Meta Temp Score: 5.0

VulDB Base Score: 2.6
VulDB Temp Score: 2.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Timing discrepancy
CWE: CWE-208 / CWE-203 / CWE-200
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: tss-lib 2.0.0

Timelineinfo

02/26/2023 🔍
04/21/2023 +53 days 🔍
04/21/2023 +0 days 🔍
07/13/2025 +814 days 🔍

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2023-26557 (🔍)
GCVE (CVE): GCVE-0-2023-26557
GCVE (VulDB): GCVE-100-227035
EUVD: 🔍

Entryinfo

Created: 04/21/2023 21:31
Updated: 07/13/2025 19:53
Changes: 04/21/2023 21:31 (41), 05/15/2023 14:32 (11), 07/13/2025 19:53 (16)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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