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Fencer Intel
high 8.8

CVE-2026-108379 json

dataclasses-avroschema fixed namespaces allow code injection in generated annotations

published 27d ago modified 24d ago also EUVD-2026-98975

cvss
8.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 28%
public exploits
0
none known

Summary

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 inserts a fixed type's namespace value between quotes inside a generated types.confixed annotation without escaping or validating it. A crafted quote can terminate the namespace string and alter the surrounding annotation expression, which Python evaluates when the generated class is defined, allowing arbitrary code execution. Version 0.70.6 fixes the vulnerability by requiring the namespace to be a dot-separated sequence of valid Avro names.

Patch / fix

Is CVE-2026-108379 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
27d ago

Exploit prediction

0.34% chance of exploitation in the next 30 days, higher than 28% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected products

  • marcosschroh dataclasses-avroschema

Classification

Weakness
  • CWE-94 Improper Control of Generation of Code

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.