SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-108384

A list is represented with quoted entries, but a bare string is emitted as an unquoted Python expression and evaluated when the generated module is imported, allowing arbitrary code execution from a crafted schema.

HIGH 8.8EPSS 0.34%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.34%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

dataclasses-avroschema generates Avro schemas from Python dataclasses, Pydantic models, and Faust Records and generates Python code from Avro schemas. From version 0.38.0 through 0.70.5, BaseGenerator.parse_fixed interpolates a fixed type's aliases value directly into a generated types.confixed annotation. A list is represented with quoted entries, but a bare string is emitted as an unquoted Python expression and evaluated when the generated module is imported, allowing arbitrary code execution from a crafted schema. Version 0.70.6 fixes the vulnerability by rejecting aliases values that are not lists.

CVSS 3.1
8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
0.34% probability · 28th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-94
Source
security-advisories@github.com
EPSS trend
0%3%5%14 October 2026: 0.34%26 October 2026: 0.34%14 October 202626 October 2026

EPSS moved from 0.3% on 14 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.