CVE-2026-11972
Description
A flaw was found in the Python tarfile module. When processing a specially crafted tar archive opened in 'streaming mode' (mode='r|'), the module does not properly handle the end-of-file (EOF) condition. This can cause the tarfile module to enter an infinite loop, leading to a Denial of Service (DoS) for applications processing such archives.
Statement
A flaw was found in the Python tarfile module. When processing a tar archive in streaming mode (mode='r|'), the _Stream.seek function does not properly check for end-of-file, which can cause an infinite loop when processing a specially crafted archive. Red Hat ships Python as part of many products, and applications using tarfile's streaming mode are potentially affected by this denial of service vulnerability.
Mitigation
Avoid using tarfile streaming mode (mode='r|') with untrusted tar archives. Use the standard file-based mode (mode='r') instead where possible.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 6.5 | N/A | N/A |
| Attack Vector | Network | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | None | N/A | N/A |
| User Interaction | Required | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Amplification
An infinite loop will cause unexpected consumption of resources, such as CPU cycles or memory. The software's operation may slow down, or cause a long time to respond.
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