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

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.

Problem type

CWE-770: Allocation of Resources Without Limits or Throttling

Affected products

kap-sh

zapros

< 0.14.0 - AFFECTED

References

https://github.com/kap-sh/zapros/security/advisories/GHSA-5vjj-2r48-q622

https://github.com/kap-sh/zapros/security/advisories/GHSA-5vjj-2r48-q622

x_refsource_CONFIRM

JSON source

https://cveawg.mitre.org/api/cve/CVE-2026-61541

Click to expand

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