Not ratedosv:MGASA-2026-0565

    Updated python3 & python-pip packages fixes security vulnerabilities

    Published Sources: OSV

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    What is affected, what to do

    CVE-2026-12345 The cleanup of tempfile.TemporaryDirectory is vulnerable to a race condition. An attacker who can modify the tree during cleanup can replace a directory with a symbolic link, causing files outside of the temporary directory to be deleted or have their permissions and file flags reset, with the privileges of the process performing the cleanup.

    The available sources name no fixed version. Check the vendor guidance in the references below.

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    Metrics

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    Priority

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    CVSS v3

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    EPSS score

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    Severity
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    Priority (0–325)

    The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?

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    30.00 Methodology
    Exploit maturity

    An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.

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    no public PoC known
    KEV status

    The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.

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    Published

    Classification under NIS2 and CRA

    Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

    NIS2

    NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.

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    Handle the vulnerability in regular vulnerability handling under Art. 21(2)(e) NIS2.
    CRA

    The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.

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    From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
    ISO/IEC 27001

    ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.

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    Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

    Description

    CVE-2026-12345 The cleanup of tempfile.TemporaryDirectory is vulnerable to a race condition. An attacker who can modify the tree during cleanup can replace a directory with a symbolic link, causing files outside of the temporary directory to be deleted or have their permissions and file flags reset, with the privileges of the process performing the cleanup. Note that platforms where shutil.rmtree.avoids_symlink_attacks is false, remain affected, and file flags may still be reset outside of the tree on all platforms. CVE-2026-19553 `ssl.SSLContext.wrap_bio()` didn't require the `server_hostname` argument to not be `None` if `ssl.SSLContext.check_hostname` was set. Due to a missing parameter check in `SSLObject`, if the `server_hostname` argument isn't supplied then hostname verification would be silently skipped. This defect could lead to programs where certificate hostname verification *appeared* to be succeeding with `SSLContext.check_hostname = True` and no `ValueError` being raised due to misconfiguration. If the program passes a `server_hostname` value that isn't an empty string or `None` to any of these APIs then certificate hostname verification proceeds as expected and the program is not affected by this vulnerability. Mitigating this vulnerability doesn't require updating Python or applying the patch. To mitigate, pass a valid non-`None` and non-empty `server_hostname` value to `SSLContext.wrap_bio()`, `asyncio.create_connection()`, or `asyncio.loop.start_tls()` and certificate hostname verification will proceed as expected. Upgrading to the latest version of Python or applying the patch only changes the behavior from silently skipping hostname verification to raising a `ValueError`, similar to `SSLContext.wrap_socket()`, when `server_hostname` isn't supplied. CVE-2026-19445 A remote, unauthenticated TLS client can make a server crash or call through a freed pointer if its sni_callback assigns a different context to SSLSocket.context (the documented way to select a certificate per server name) and nothing else keeps the original ssl.SSLContext alive. Typical cases are servers that create an SSLContext per connection or replace it while connections are open; servers that wrap their listening socket with it are not affected. Mitigation: keep a reference to every SSLContext that sets sni_callback for the lifetime of the server. TLS clients are not affected. CVE-2026-114583 tarfile.tar_filter could be bypassed using crafted link entries, including symlinks with empty or directory-like names, to redirect later archive members outside the intended extraction directory. This allowed a malicious tar archive to cause tarfile.extractall() with filter="tar" to write files outside the destination directory, subject to the permissions of the extracting process. This is the tarfile.tar_filter counterpart of CVE-2026-7774, which covered tarfile.data_filter.

    Source: OSV (Open Source Vulnerabilities)