CVE-2024-24560 | Vyper external calls can overflow return data to return input buffer

Exp

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.

Published: 2024-02-02 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2024-24560 is rated Exploit Available (56.5/100): CVSS Low severity, with medium exploitation likelihood (EPSS 0.92%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2024-24560

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2024-24560

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-02-20 0.64% 0.92% +0.27%
2 2025-11-21 0.22% 0.64% +0.43%
3 2025-11-18 0.22%

Full EPSS history (11 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-24560

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
3.7 3.1 LOW
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
2.2 1.4 [email protected]
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/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:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 1.4 [email protected]

Weakness enumeration for CVE-2024-24560

GitHub Security Advisory for CVE-2024-24560

GHSA-gp3w-2v2m-p686 · Severity: low · Ecosystem: pip — Vyper's external calls can overflow return data to return input buffer

Affected software / configurations for CVE-2024-24560

Vendor Product Version Raw CPE
vyperlang vyper <= 0.3.10 cpe:2.3:a:vyperlang:vyper:*:*:*:*:*:python:*:*

References for CVE-2024-24560

cvelogic Threat Intelligence