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CVE-2026-61541PYSEC-2026-4181GHSA-5VJJ-2R48-Q622

Zapros has an Unbounded Content-Encoding decompression chain that allows denial of service

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 0.14.0
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: none
  • Automatable: yes
  • Technical impact: partial

Summary

Zapros, a Python HTTP client, prior to version 0.14.0 is vulnerable to denial of service when an application requests content from an untrusted server, or follows a redirect to one, because a malicious response containing an excessive number of chained `Content-Encoding` values causes Zapros to construct a deeply nested decompression chain that consumes excessive resources. Version 0.14.0 patches the vulnerability by limiting responses to five content-encoding layers and raising `DecodingError` when that limit is exceeded. As a workaround, applications can add response middleware that inspects the `Content-Encoding` header and rejects responses containing more than a safe number of encoding layers.

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: none · Automatable: yes · Technical impact: partial

  3. Record last updated

Affected versions

  • kap-sh zapros

    fixed in 0.14.0

  • zaprosPyPI

    fixed in 0.14.0

References 1

GitHub · kap-sh/zapros