CVE-2026-61541 (GCVE-0-2026-61541)

Vulnerability from cvelistv5 – Published: 2026-09-21 21:21 – Updated: 2026-09-21 21:21
VLAI
Title
Zapros has an Unbounded Content-Encoding decompression chain that allows denial of service
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.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
References
Impacted products
Vendor Product Version CPE status
kap-sh zapros Affected: < 0.14.0
guessed Create a notification for this product.
Show details on NVD website
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        }
      ],
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    "dateReserved": "2026-07-10T16:27:03.093Z",
    "dateUpdated": "2026-09-21T21:21:21.321Z",
    "state": "PUBLISHED"
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        "lastModified": "2026-09-21T22:16:57.527",
        "metrics": {
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                "exploitMaturity": "NOT_DEFINED",
                "integrityRequirement": "NOT_DEFINED",
                "modifiedAttackComplexity": "NOT_DEFINED",
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                "modifiedAttackVector": "NOT_DEFINED",
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                "modifiedSubAvailabilityImpact": "NOT_DEFINED",
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}



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