SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAwaiting Analysis

CVE-2026-114115

Vyper 0.3.8 through 0.5.0b1 contains a compiler miscompilation vulnerability in parse_IfExp that reads nested arrays with narrower inner bounds using the wider result type's memory layout.

MEDIUM 6.3EPSS 0.28%

Does this matter?

Lower severity and a low EPSS score (0.28%). Track it; it rarely justifies an emergency change on its own.

Description

Vyper 0.3.8 through 0.5.0b1 contains a compiler miscompilation vulnerability in parse_IfExp that reads nested arrays with narrower inner bounds using the wider result type's memory layout. When a ternary selects the narrower array, inner arrays after the first are read at wrong offsets, causing contracts to silently store corrupted values or revert.

CVSS 4.0
6.3 MEDIUMCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/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/M
EPSS
0.28% probability · 20th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-843
Source
disclosure@vulncheck.com
EPSS trend
0%3%5%21 October 2026: 0.22%26 October 2026: 0.28%21 October 202626 October 2026

EPSS moved from 0.2% on 21 October 2026 to 0.3% on 26 October 2026.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.