CVE-2020-6174
Incorrect threshold signature computation in TUF
CVE-2020-6174 is a critical vulnerability (CVSS 9.8) in Linuxfoundation The Update Framework, published February 5, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.99%, the 62nd percentile. Fixed in tuf 0.12.2.
- Severity
- 9.8 CriticalCVSS 3.1, NVD
- Exploit chance
- 0.99%EPSS, 62nd percentile
- Exploitation
- None knownNot on CISA’s or ENISA’s lists
- Fixed in
0.12.2tuf +2 more
Description
TUF (aka The Update Framework) through 0.12.1 has Improper Verification of a Cryptographic Signature.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
tufPyPI | before 0.12.2 | 0.12.2 |
tufPyPI | before 0.12.2, plus listed versions 0.10.00.10.10.10.20.11.00.11.1 Show 12 moreShow less0.11.2.dev10.11.2.dev20.11.2.dev30.11.dev00.12.00.12.10.12.dev00.12.dev10.12.dev20.7.50.9.80.9.9 | 0.12.2 |
tufPyPI | before 0.12.2, plus listed versions 0.7.50.9.80.9.90.10.00.10.1 Show 12 moreShow less0.10.20.11.dev00.11.00.11.10.11.2.dev10.11.2.dev20.11.2.dev30.12.dev00.12.dev10.12.dev20.12.00.12.1 | 0.12.2 |
What each source reports
NVD Score used
TUF (aka The Update Framework) through 0.12.1 has Improper Verification of a Cryptographic Signature.
- Record
CVE-2020-6174- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-347
- Updated
- 2026-11-02
CVE ListNo score
TUF (aka The Update Framework) through 0.12.1 has Improper Verification of a Cryptographic Signature.
- Record
CVE-2020-6174- Updated
- 2026-11-02
EUVDEUVD-2020-0226No score
TUF (aka The Update Framework) through 0.12.1 has Improper Verification of a Cryptographic Signature.
- Record
EUVD-2020-0226- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-pwqf-9h7j-7mv8
Incorrect threshold signature computation in TUF
Impact
Metadadata signature verification, as used in tuf.client.updater, counted each of multiple signatures with identical authorized keyids separately towards the threshold. Therefore, an attacker with access to a valid signing key could create multiple valid signatures in order to meet the minimum threshold of keys before the metadata was considered valid.
The tuf maintainers would like to thank Erik MacLean of Analog Devices, Inc. for reporting this issue.
Patches
A fix is available in version 0.12.2 or newer.
Workarounds
No workarounds are known for this issue.
References
- CVE-2020-6174
- Pull request resolving the issue PR 974
- Record
GHSA-pwqf-9h7j-7mv8- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-347
- Updated
- 2026-11-02
OSV
TUF (aka The Update Framework) through 0.12.1 has Improper Verification of a Cryptographic Signature.
- Record
CVE-2020-6174- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVGHSA-pwqf-9h7j-7mv8
Incorrect threshold signature computation in TUF
Impact
Metadadata signature verification, as used in tuf.client.updater, counted each of multiple signatures with identical authorized keyids separately towards the threshold. Therefore, an attacker with access to a valid signing key could create multiple valid signatures in order to meet the minimum threshold of keys before the metadata was considered valid.
The tuf maintainers would like to thank Erik MacLean of Analog Devices, Inc. for reporting this issue.
Patches
A fix is available in version 0.12.2 or newer.
Workarounds
No workarounds are known for this issue.
References
- CVE-2020-6174
- Pull request resolving the issue PR 974
- Record
GHSA-pwqf-9h7j-7mv8- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-347
- Updated
- 2026-11-02
OSVPYSEC-2020-147No score
TUF (aka The Update Framework) through 0.12.1 has Improper Verification of a Cryptographic Signature.
- Record
PYSEC-2020-147- Updated
- 2026-11-02
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | ||
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
References
github.com/theupdateframework/tuf/pull/974
nvd.nist.gov/vuln/detail/CVE-2020-6174