Cyber Resilience

CVE-2025-8194

HighDDoS

Published: 28 July 2025

Published
28 July 2025
Modified
15 April 2026
KEV Added
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Patch
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CVSS Score v3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0101 77.5th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-8194 is a high-severity Infinite Loop (CWE-835) vulnerability in Python (inferred from references). Its CVSS base score is 7.5 (High).

Operationally, ranked in the top 22.5% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

Deeper analysis

CVE-2025-8194 is a defect in the CPython tarfile module that affects the TarFile extraction and entry enumeration APIs. The tar implementation accepts archives containing negative offsets without raising an error, which triggers an infinite loop and deadlock when parsing a maliciously crafted tar file. The issue is tracked under CWE-835 and carries a CVSS 3.1 score of 7.5 reflecting high availability impact.

An unauthenticated remote attacker can supply a specially constructed tar archive to any application that uses the affected TarFile interfaces for extraction or listing. Successful exploitation causes the consuming process to hang indefinitely, resulting in denial of service without requiring authentication or user interaction.

The supplied mitigation consists of applying the patch referenced in the GitHub gist immediately after importing the tarfile module; several corrective commits have also been merged into the CPython repository. The EPSS score has remained flat at 0.0101 with no material increase observed since disclosure.

EU & UK References

Vulnerability details

There is a defect in the CPython “tarfile” module affecting the “TarFile” extraction and entry enumeration APIs. The tar implementation would process tar archives with negative offsets without error, resulting in an infinite loop and deadlock during the parsing of…

more

maliciously crafted tar archives. This vulnerability can be mitigated by including the following patch after importing the “tarfile” module: https://gist.github.com/sethmlarson/1716ac5b82b73dbcbf23ad2eff8b33e1

CWE(s)
CWE-835

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

Python
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inferred from references and description; NVD did not file a CPE for this CVE

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

CP-7 Alternate Processing Site
addresses: CWE-835

Enables transfer to alternate site if an infinite loop at the primary renders processing unavailable.

SC-5 Denial-of-service Protection
addresses: CWE-835

Detects and mitigates infinite loops that produce sustained resource consumption.

References