CVE-2021-48018
Vyper 0.2.13 before 0.2.15 Storage Corruption via @nonreentrant Decorator
Vyper from 0.2.13 before 0.2.15 allocates storage slots for @nonreentrant reentrancy locks at the same locations as contract storage variables. When a function using @nonreentrant is called, setting the lock overwrites the overlapping storage variable, corrupting contract state and breaking the contract's intended logic.
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
- None
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Vyper 0.2.13 before 0.2.15 Storage Corruption via @nonreentrant Decorator
Vyper from 0.2.13 before 0.2.15 allocates storage slots for @nonreentrant reentrancy locks at the same locations as contract storage variables. When a function using @nonreentrant is called, setting the lock overwrites the overlapping storage variable, corrupting contract state and breaking the contract's intended logic.
- Record
CVE-2021-48018- CVSS 4.0
- 8.3 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 7.4 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
EUVDEUVD-2021-34888
Vyper from 0.2.13 before 0.2.15 allocates storage slots for @nonreentrant reentrancy locks at the same locations as contract storage variables. When a function using @nonreentrant is called, setting the lock overwrites the overlapping storage variable, corrupting contract state and breaking the contract's intended logic.
- Record
EUVD-2021-34888- CVSS 4.0
- 8.3 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-57w3-rr8j-wp9c
Vyper from 0.2.13 before 0.2.15 allocates storage slots for @nonreentrant reentrancy locks at the...
Vyper from 0.2.13 before 0.2.15 allocates storage slots for @nonreentrant reentrancy locks at the same locations as contract storage variables. When a function using @nonreentrant is called, setting the lock overwrites the overlapping storage variable, corrupting contract state and breaking the contract's intended logic.
- Record
GHSA-57w3-rr8j-wp9c- CVSS 4.0
- 8.3 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.4 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
GitHub AdvisoriesGHSA-7f92-rr6w-cq64 No score
Storage corruption due to variables overwritten by re-entrancy locks
Background
When attempting to use the v0.2.14 release, @pandadefi discovered an issue using the @nonreentrant decorator.
Impact
Reentrancy protection storage slots get allocated to the same slots as storage variables, leading to the corruption of storage variables when using the @nonreentrant decorator.
Patches
This issue was fixed in v0.2.15 in #2391, #2379
Workarounds
Don't use the @nonreentrant decorator in these versions.
- Record
GHSA-7f92-rr6w-cq64- Updated
- 2026-11-02
NVD
Vyper from 0.2.13 before 0.2.15 allocates storage slots for @nonreentrant reentrancy locks at the same locations as contract storage variables. When a function using @nonreentrant is called, setting the lock overwrites the overlapping storage variable, corrupting contract state and breaking the contract's intended logic.
- Record
CVE-2021-48018- CVSS 4.0
- 8.3 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.4 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
OSV
Vyper from 0.2.13 before 0.2.15 allocates storage slots for @nonreentrant reentrancy locks at the same locations as contract storage variables. When a function using @nonreentrant is called, setting the lock overwrites the overlapping storage variable, corrupting contract state and breaking the contract's intended logic.
- Record
CVE-2021-48018- CVSS 4.0
- 8.3 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Updated
- 2026-11-02
OSVGHSA-7f92-rr6w-cq64 No score
Storage corruption due to variables overwritten by re-entrancy locks
Background
When attempting to use the v0.2.14 release, @pandadefi discovered an issue using the @nonreentrant decorator.
Impact
Reentrancy protection storage slots get allocated to the same slots as storage variables, leading to the corruption of storage variables when using the @nonreentrant decorator.
Patches
This issue was fixed in v0.2.15 in #2391, #2379
Workarounds
Don't use the @nonreentrant decorator in these versions.
- Record
GHSA-7f92-rr6w-cq64- Updated
- 2026-11-02
Affected products
Affected packages
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-48018 is a high vulnerability (CVSS 8.3) in Vyperlang Vyper, published August 5, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.39%, the 33rd percentile. Fixed in vyper 0.2.15.
References
github.com/vyperlang/vyper/security/advisories/GHSA-7f92-rr6w-cq64
vulncheck.com/advisories/vyper-0.2.13-before-0.2.15-storage-corruption-via-nonreentrant-decorator
nvd.nist.gov/vuln/detail/CVE-2021-48018