CVE-2024-24560 json
Vyper external calls can overflow return data to return input buffer
published 2024-02-02 2 y ago modified 2026-09-10 1 mo ago also GHSA-gp3w-2v2m-p686 , PYSEC-2024-148 , EUVD-2024-0175
- cvss
- 3.7
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 44%
- public exploits
- 0
- none known
Summary
Vyper is a Pythonic Smart Contract Language for the Ethereum Virtual Machine. When calls to external contracts are made, we write the input buffer starting at byte 28, and allocate the return buffer to start at byte 0 (overlapping with the input buffer). When checking RETURNDATASIZE for dynamic types, the size is compared only to the minimum allowed size for that type, and not to the returned value's length. As a result, malformed return data can cause the contract to mistake data from the input buffer for returndata. When the called contract returns invalid ABIv2 encoded data, the calling contract can read different invalid data (from the dirty buffer) than the called contract returned.
Patch / fix
- pypi vyper 0.4.0, 0.4.0b1
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 2 y ago
Exploit prediction
0.53% chance of exploitation in the next 30 days, higher than 44% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/vyperlang/vyper/security/advisories/GHSA-gp3w-2v2m-p686 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N |
| NVD | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |
| OSV | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |
| GitHub | 3.1 | 3.7 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | vyper | <0.4.0 <0.4.0b1 |
0.4.0 0.4.0b1 |
Affected products
- vyperlang vyper
Classification
- Weakness
-
- CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer
References
-
github.com
/vyperlang/vyper/security/advisories/GHSA-gp3w-2v2m-p686
web, exploit, vendor-advisory, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2024-24560
advisory
-
github.com
/pypa/advisory-database/tree/main/vulns/vyper/PYSEC-2024-148.yaml
web
-
github.com
/vyperlang/vyper
package
Sources
- CVE List CVE-2024-24560
- GitHub Advisory GHSA-gp3w-2v2m-p686
- NVD CVE-2024-24560
- OSV PYSEC-2024-148
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