CVE-2026-61541 json
Zapros has an Unbounded Content-Encoding decompression chain that allows denial of service
published 2026-09-21 48 d ago modified 2026-10-01 38 d ago also GHSA-5vjj-2r48-q622 , PYSEC-2026-4181 , EUVD-2026-84182
- cvss
- 6.9
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 37%
- public exploits
- 0
- none known
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.
Patch / fix
- pypi zapros 0.14.0
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 46 d ago
Exploit prediction
0.43% chance of exploitation in the next 30 days, higher than 37% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 6.9 | 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 |
| CNA | 4.0 | 6.9 | 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | zapros | <0.14.0 |
0.14.0 |
Affected products
- kap-sh zapros
Classification
- Weakness
-
- CWE-770 Allocation of Resources Without Limits or Throttling
References
-
github.com
/kap-sh/zapros/commit/7971fbca9707eb01455ca2d73416ac091f96908b
web
-
github.com
/kap-sh/zapros/security/advisories/GHSA-5vjj-2r48-q622
web
-
nvd.nist.gov
/vuln/detail/CVE-2026-61541
advisory
-
github.com
/kap-sh/zapros
package
-
github.com
/kap-sh/zapros/releases/tag/v0.14.0
web
-
pypi.org
/project/zapros
package
-
github.com
/advisories/GHSA-5vjj-2r48-q622
advisory
Sources
- CVE List CVE-2026-61541
- GitHub Advisory GHSA-5vjj-2r48-q622
- NVD CVE-2026-61541
- OSV PYSEC-2026-4181
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