OpenZeppelin Contracts's GovernorVotesQuorumFraction updates to quorum may affect past defeated proposals

Description

Impact

This issue concerns instances of Governor that use the module GovernorVotesQuorumFraction, a mechanism that determines quorum requirements as a percentage of the voting token's total supply. In affected instances, when a proposal is passed to lower the quorum requirement, past proposals may become executable if they had been defeated only due to lack of quorum, and the number of votes it received meets the new quorum requirement.

Analysis of instances on chain found only one proposal that met this condition, and we are actively monitoring for new occurrences of this particular issue.

Patches

This issue has been patched in v4.7.2.

Workarounds

Avoid lowering quorum requirements if a past proposal was defeated for lack of quorum.

References

https://github.com/OpenZeppelin/openzeppelin-contracts/pull/3561

For more information

If you have any questions or comments about this advisory, or need assistance deploying the fix, email us at [email protected].

Basic information

Type
reviewed
Severity
high
Advisory on GitHub
Open advisory ↗
Repository advisory
Open repository advisory ↗
Source code
Browse source ↗
Published (advisory)
2022-08-18 18:48:41 UTC
Updated
2023-01-30 05:06:59 UTC
GitHub reviewed
2022-08-18 18:48:41 UTC
NVD published
2022-08-01

EPSS Score

Score Percentile
0.27% 49.85%

CVSS Scores

Base score Version Severity Vector
7.5 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.

Identifiers

CWEs

CWE id Name
CWE-682 Incorrect Calculation

Affected packages (2)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
npm @openzeppelin/contracts >= 4.3.0, < 4.7.2 4.7.2
npm @openzeppelin/contracts-upgradeable >= 4.3.0, < 4.7.2 4.7.2

References

cvelogic Threat Intelligence