libexpat before 2.7.5 allows an infinite loop while parsing DTD content.

The remote openSUSE 16 host has packages installed that are affected by multiple vulnerabilities as referenced in the openSUSE-SU-2026:20448-1 advisory.

    - CVE-2026-32776: NULL pointer dereference when processing empty external parameter entities inside an     entity       declaration value (bsc#1259726).
    - CVE-2026-32777: denial of service due to infinite loop in DTD content parsing (bsc#1259711).
    - CVE-2026-32778: NULL pointer dereference in `setContext` on retry after an out-of-memory condition       (bsc#1259729).

Tenable has extracted the preceding description block directly from the SUSE 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 remote SUSE Linux SLES15 / SLES_SAP15 / openSUSE 15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:1166-1 advisory.

    - CVE-2026-32776: NULL pointer dereference when processing empty external parameter entities inside an     entity       declaration value (bsc#1259726).
    - CVE-2026-32777: denial of service due to infinite loop in DTD content parsing (bsc#1259711).
    - CVE-2026-32778: NULL pointer dereference in `setContext` on retry after an out-of-memory condition     (bsc#1259729).

Tenable has extracted the preceding description block directly from the SUSE 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 version of firefox installed on the remote host is prior to 140.8.0-1. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2FIREFOX-2026-055 advisory.

    A flaw was found in libexpat. A remote attacker could exploit this vulnerability by providing specially     crafted XML content with empty external parameter entities. This could lead to a NULL pointer dereference,     causing the application to crash and resulting in a Denial of Service (DoS). (CVE-2026-32776)

    A flaw was found in libexpat. A remote attacker could exploit this vulnerability by providing specially     crafted Document Type Definition (DTD) content. This could lead to an infinite loop during parsing,     resulting in a Denial of Service (DoS) for the application using libexpat. (CVE-2026-32777)

    A flaw was found in libexpat. This vulnerability allows an attacker to trigger a NULL pointer dereference     in the `setContext` function. This occurs when the system attempts to retry an operation after an out-of-     memory condition, which can lead to a Denial of Service (DoS) for the affected application.
    (CVE-2026-32778)

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 version of thunderbird installed on the remote host is prior to 140.8.0-1. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2-2026-3219 advisory.

    A flaw was found in libexpat. A remote attacker could exploit this vulnerability by providing specially     crafted XML content with empty external parameter entities. This could lead to a NULL pointer dereference,     causing the application to crash and resulting in a Denial of Service (DoS). (CVE-2026-32776)

    A flaw was found in libexpat. A remote attacker could exploit this vulnerability by providing specially     crafted Document Type Definition (DTD) content. This could lead to an infinite loop during parsing,     resulting in a Denial of Service (DoS) for the application using libexpat. (CVE-2026-32777)

    A flaw was found in libexpat. This vulnerability allows an attacker to trigger a NULL pointer dereference     in the `setContext` function. This occurs when the system attempts to retry an operation after an out-of-     memory condition, which can lead to a Denial of Service (DoS) for the affected application.
    (CVE-2026-32778)

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 ALAS2023-2026-1518 advisory.

    A flaw was found in libexpat. A remote attacker could exploit this vulnerability by providing specially     crafted XML content with empty external parameter entities. This could lead to a NULL pointer dereference,     causing the application to crash and resulting in a Denial of Service (DoS). (CVE-2026-32776)

    A flaw was found in libexpat. A remote attacker could exploit this vulnerability by providing specially     crafted Document Type Definition (DTD) content. This could lead to an infinite loop during parsing,     resulting in a Denial of Service (DoS) for the application using libexpat. (CVE-2026-32777)

    A flaw was found in libexpat. This vulnerability allows an attacker to trigger a NULL pointer dereference     in the `setContext` function. This occurs when the system attempts to retry an operation after an out-of-     memory condition, which can lead to a Denial of Service (DoS) for the affected application.
    (CVE-2026-32778)

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 remote SUSE Linux SLES12 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:1159-1 advisory.

    - CVE-2026-32776: NULL pointer dereference when processing empty external parameter entities inside an     entity       declaration value (bsc#1259726).
    - CVE-2026-32777: denial of service due to infinite loop in DTD content parsing (bsc#1259711).
    - CVE-2026-32778: NULL pointer dereference in `setContext` on retry after an out-of-memory condition     (bsc#1259729).

Tenable has extracted the preceding description block directly from the SUSE 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 remote Fedora 42 host has a package installed that is affected by a vulnerability as referenced in the FEDORA-2026-1cbd107c34 advisory.

    Update to 2.7.5.

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

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

The remote Fedora 43 host has a package installed that is affected by a vulnerability as referenced in the FEDORA-2026-e70c1919fe advisory.

    Update to 2.7.5.

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

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

The remote Fedora 44 host has a package installed that is affected by a vulnerability as referenced in the FEDORA-2026-cf814a1a06 advisory.

    Update to 2.7.5.

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

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

The version of expat installed on the remote host is prior to 2.7.5. It is, therefore, affected by multiple vulnerabilities as referenced in the SSA:2026-077-01 advisory.

    New expat packages are available for Slackware 15.0 and -current to fix security issues.

Tenable has extracted the preceding description block directly from the expat 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.

  - libexpat before 2.7.5 allows an infinite loop while parsing DTD content. (CVE-2026-32777)

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

ID	Name	Product	Family	Severity
304865	openSUSE 16 Security Update : expat (openSUSE-SU-2026:20448-1)	Nessus	SuSE Local Security Checks	medium
304857	SUSE SLES15 / openSUSE 15 Security Update : expat (SUSE-SU-2026:1166-1)	Nessus	SuSE Local Security Checks	medium
304599	Amazon Linux 2 : firefox, --advisory ALAS2FIREFOX-2026-055 (ALASFIREFOX-2026-055)	Nessus	Amazon Linux Local Security Checks	medium
304586	Amazon Linux 2 : thunderbird, --advisory ALAS2-2026-3219 (ALAS-2026-3219)	Nessus	Amazon Linux Local Security Checks	medium
304582	Amazon Linux 2023 : firefox (ALAS2023-2026-1518)	Nessus	Amazon Linux Local Security Checks	medium
304483	SUSE SLES12 Security Update : expat (SUSE-SU-2026:1159-1)	Nessus	SuSE Local Security Checks	medium
304312	Fedora 42 : mingw-expat (2026-1cbd107c34)	Nessus	Fedora Local Security Checks	medium
304253	Fedora 43 : mingw-expat (2026-e70c1919fe)	Nessus	Fedora Local Security Checks	medium
304252	Fedora 44 : mingw-expat (2026-cf814a1a06)	Nessus	Fedora Local Security Checks	medium
302921	Slackware Linux 15.0 / current expat Multiple Vulnerabilities (SSA:2026-077-01)	Nessus	Slackware Local Security Checks	medium
302508	Linux Distros Unpatched Vulnerability : CVE-2026-32777	Nessus	Misc.	medium

Detections

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CVE-2026-32777

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Tenable Plugins

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