CVE-2020-15093Published

Improper verification of signature threshold in tough

Collected exploitation and prediction evidence

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

cve-program · CVE-2020-15093

Published

The tough library (Rust/crates.io) prior to version 0.7.1 does not properly verify the threshold of cryptographic signatures. It allows an attacker to duplicate a valid signature in order to circumvent TUF requiring a minimum threshold of unique signatures before the metadata is considered valid. A fix is available in version 0.7.1. CVE-2020-6174 is assigned to the same vulnerability in the TUF reference implementation.

Source published: 9 Jul 2020 18:45:16 UTC
Source modified: 4 Aug 2024 13:08:21 UTC
Observed here: 23 Oct 2026 15:48:27 UTC
Source terms: CVE Program Terms of Use

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CVSS 3.1 · 8.6 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N

euvd · EUVD-2021-1579

Published

EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.

Original publisher date fields

datePublished: Jul 9, 2020, 6:45:16 PM

dateUpdated: Aug 4, 2024, 1:08:21 PM

Source published: Jul 9, 2020, 6:45:16 PM (timezone not stated)
Source modified: Aug 4, 2024, 1:08:21 PM (timezone not stated)
Observed here: 9 Nov 2026 20:07:04 UTC
Source terms: ENISA EUVD · source terms and attribution apply

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EUVD CVSS 3.1 · 8.6 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N

nvd · CVE-2020-15093

Published

NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.

Source analysis status: Modified

Weakness classifications: CWE-347

Original publisher date fields

published: 2020-07-09T19:15:11.413

lastModified: 2026-06-17T02:56:02.333

1 source CPE criteria · context only

cpe:2.3:a:amazon:tough:*:*:*:*:*:rust:*:*

The original JSON retains the logical configuration operators, exclusions and version bounds.

Source published: 9 Jul 2020 19:15:11 UTC
Source modified: 17 Jun 2026 02:56:02 UTC
Observed here: 24 Oct 2026 16:17:20 UTC
Source terms: NIST NVD usage terms; underlying source attribution retained

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CVSS 3.1 · [email protected] · Secondary · 8.6 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N

CVSS 3.1 · [email protected] · Primary · 8.6 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N

CVSS 2.0 · [email protected] · Primary · 5.0 AV:N/AC:L/Au:N/C:N/I:P/A:N

osv · GHSA-5q2r-92f9-4m49

Published

## Impact The tough library, prior to 0.7.1, does not properly verify the uniqueness of keys in the signatures provided to meet the threshold of cryptographic signatures. It allows someone with access to a valid signing key to create multiple valid signatures in order to circumvent TUF requiring a minimum threshold of unique keys before the metadata is considered valid. AWS would like to thank Erick Tryzelaar of the Google Fuchsia Team for reporting this issue. ## Patches A fix is available in version 0.7.1. ## Workarounds No workarounds to this issue are known. ## References CVE-2020-6174 is assigned to the same issue in the TUF reference implementation. https://github.com/theupdateframework/tuf/pull/974 https://nvd.nist.gov/vuln/detail/CVE-2020-6174 ## For more information If you have any questions or comments about this advisory, [contact AWS Security](https://aws.amazon.com/security/vulnerability-reporting/) at [[email protected]](mailto:[email protected]).

Source published: 25 Aug 2021 20:56:55 UTC
Source modified: 8 Jul 2026 06:29:16 UTC
Observed here: 24 Oct 2026 13:19:54 UTC
Source terms: GitHub Advisory Database · CC-BY-4.0

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N

Publisher rating · HIGH

osv · RUSTSEC-2020-0024

Published

The tough library, prior to 0.7.1, does not properly verify the uniqueness of keys in the signatures provided to meet the threshold of cryptographic signatures. It allows someone with access to a valid signing key to create multiple valid signatures in order to circumvent TUF requiring a minimum threshold of unique keys before the metadata is considered valid. AWS would like to thank Erick Tryzelaar of the Google Fuchsia Team for reporting this issue. A fix is available in version 0.7.1. CVE-2020-6174 is assigned to the same issue in the TUF reference implementation. If you have any questions or comments about this advisory, contact AWS Security at [email protected].

Source published: 9 Jul 2020 12:00:00 UTC
Source modified: 12 Oct 2026 18:00:05 UTC
Observed here: 24 Oct 2026 13:19:54 UTC
Source terms: OSV · upstream source license applies

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · OSV · upstream source license applies. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N