Attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing and consume significant CPU when applications pass unbounded input to csv.Sniffer.sniff().

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2026-2122 advisory.

    Attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing     and consume significant CPU when applications pass unbounded input to csv.Sniffer.sniff().
    (CVE-2026-18503)

    `Element.findall()` and fully-consumed `Element.iterfind()` exhibit `O(n^2)` time complexity when using     XPath index predicates (e.g. `[1]`, `[last()]`, `[last()-N]`) on XML documents with many same-tag     siblings. `Element.find()` is only affected when the first match is near the end  of the sibling list,     such as with `[last()]` or `[last()-N]`;  `.//item[1]` short-circuits after the first match.
    (CVE-2026-6879)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2026-2123 advisory.

    Attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing     and consume significant CPU when applications pass unbounded input to csv.Sniffer.sniff().
    (CVE-2026-18503)

    `Element.findall()` and fully-consumed `Element.iterfind()` exhibit `O(n^2)` time complexity when using     XPath index predicates (e.g. `[1]`, `[last()]`, `[last()-N]`) on XML documents with many same-tag     siblings. `Element.find()` is only affected when the first match is near the end  of the sibling list,     such as with `[last()]` or `[last()-N]`;  `.//item[1]` short-circuits after the first match.
    (CVE-2026-6879)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2026-2124 advisory.

    Attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing     and consume significant CPU when applications pass unbounded input to csv.Sniffer.sniff().
    (CVE-2026-18503)

    `Element.findall()` and fully-consumed `Element.iterfind()` exhibit `O(n^2)` time complexity when using     XPath index predicates (e.g. `[1]`, `[last()]`, `[last()-N]`) on XML documents with many same-tag     siblings. `Element.find()` is only affected when the first match is near the end  of the sibling list,     such as with `[last()]` or `[last()-N]`;  `.//item[1]` short-circuits after the first match.
    (CVE-2026-6879)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2026-2125 advisory.

    Attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing     and consume significant CPU when applications pass unbounded input to csv.Sniffer.sniff().
    (CVE-2026-18503)

    `Element.findall()` and fully-consumed `Element.iterfind()` exhibit `O(n^2)` time complexity when using     XPath index predicates (e.g. `[1]`, `[last()]`, `[last()-N]`) on XML documents with many same-tag     siblings. `Element.find()` is only affected when the first match is near the end  of the sibling list,     such as with `[last()]` or `[last()-N]`;  `.//item[1]` short-circuits after the first match.
    (CVE-2026-6879)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - Attacker-controlled CSV samples can trigger super-linear regular-expression work during dialect sniffing     and consume significant CPU when applications pass unbounded input to csv.Sniffer.sniff().
    (CVE-2026-18503)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Type	Severity
342050	Amazon Linux 2023 : python3.14, python3.14-devel, python3.14-freethreading (ALAS2023-2026-2122)	Nessus	Amazon Linux Local Security Checks	Local	low
342049	Amazon Linux 2023 : python3.13, python3.13-devel, python3.13-freethreading (ALAS2023-2026-2123)	Nessus	Amazon Linux Local Security Checks	Local	low
342048	Amazon Linux 2023 : python3.12, python3.12-devel, python3.12-idle (ALAS2023-2026-2124)	Nessus	Amazon Linux Local Security Checks	Local	low
341864	Amazon Linux 2023 : python3.11, python3.11-devel, python3.11-idle (ALAS2023-2026-2125)	Nessus	Amazon Linux Local Security Checks	Local	low
335028	Linux Distros Unpatched Vulnerability : CVE-2026-18503	Nessus	Misc.	Local	low

Detections

Analytics

CVE-2026-18503

low

Tenable Plugins

low

low

low

low

low