Resource allocation without limits in kap-sh zapros
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-770.
Summary
Zapros, a Python HTTP client, prior to version 0.14.0 is vulnerable to denial of service via memory exhaustion. The issue affects all callers who streamed compressed responses relying on the chunk size — explicit (`iter_bytes(chunk_size=...)`) or the default — to bound memory. The decoder ignored that bound, so a chunk could be far larger than requested and a single compressed response could overflow memory. Version 0.14.0 contains a patch. Some workarounds are available. Read the still-compressed body with `Response.iter_raw()` / `Response.async_iter_raw()`, which bypass the built-in decoders, and decompress it yourself with an explicit output-size bound (e.g. `zlib`'s `max_length`), aborting once a configured limit is exceeded. Where feasible, send `Accept-Encoding: identity` to disable response compression so bodies are not decompressed client-side. Avoid decoding response bodies from untrusted servers.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| kap-sh | zapros | before 0.14.0 | 0.14.0 | Patch available | CNA |
| — | zapros (PyPI) | before 0.14.0 | 0.14.0 | Patch available | GHSA-6cp7-3m3c-5x5c |
- zapros Vendorkap-sh Affected before 0.14.0 Fixed in 0.14.0 Patch available CNA
- zapros (PyPI) Vendor— Affected before 0.14.0 Fixed in 0.14.0 Patch available GHSA-6cp7-3m3c-5x5c
Remediation
- Fix · CNA zapros (kap-sh) Fixed in 0.14.0
- Fix · GHSA-6cp7-3m3c-5x5c zapros (PyPI) Fixed in 0.14.0 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-61652
- 2026-10-03 Alias added: GHSA-6cp7-3m3c-5x5c
References
More kap-sh vulnerabilities
- TI-2026-44101 Zapros has an Unbounded Content-Encoding decompression chain that allows denial of service CVSS 4.0MEDIUM 6.9
Sources
- CVE-2026-61652 · CVE Program
- CVE-2026-61652 · NVD
- FIRST EPSS
- GHSA-6cp7-3m3c-5x5c · GitHub Advisory Database · CC BY 4.0
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