# CVE-2025-46420: Libsoup: memory leak on soup_header_parse_quality_list() via soup-headers.c

Status: published. Published: 2025-04-24. Updated: 2026-11-05.

A flaw was found in libsoup. It is vulnerable to memory leaks in the soup_header_parse_quality_list() function when parsing a quality list that contains elements with all zeroes.

## Remediation

- workaround: Currently, no mitigation is available for this vulnerability. (source: CNA: redhat)

## Affected products and versions

-  /  (libsoup): ≥ 0; < 3.6.3 (affected, semver). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (libsoup): ≥ 0:2.62.3-8.el8_10; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.2 Advanced Update Support (libsoup): ≥ 0:2.62.3-1.el8_2.4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support (libsoup): ≥ 0:2.62.3-2.el8_4.4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.4 Telecommunications Update Service (libsoup): ≥ 0:2.62.3-2.el8_4.4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions (libsoup): ≥ 0:2.62.3-2.el8_4.4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support (libsoup): ≥ 0:2.62.3-2.el8_6.4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Telecommunications Update Service (libsoup): ≥ 0:2.62.3-2.el8_6.4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions (libsoup): ≥ 0:2.62.3-2.el8_6.4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.8 Extended Update Support (libsoup): ≥ 0:2.62.3-3.el8_8.4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (libsoup): ≥ 0:2.72.0-10.el9_6.1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions (libsoup): ≥ 0:2.72.0-8.el9_0.4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.2 Extended Update Support (libsoup): ≥ 0:2.72.0-8.el9_2.4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.4 Extended Update Support (libsoup): ≥ 0:2.72.0-8.el9_4.4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 10 (libsoup3): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 6 (libsoup): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (libsoup): Version range not reported. Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 6.5 (medium); CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H; source: CNA: redhat

- CVSS 3.1: 6.5 (medium); CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H; source: NVD: secalert@redhat.com

- CISA KEV: No listing in collected sources

- EPSS: 0.59% as of 2026-11-05; percentile 48.56%

- SSVC: exploitation none; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-401

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://access.redhat.com/errata/RHSA-2025:4439 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:4440 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:4508 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:4538 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:4560 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:4568 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:4609 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:4624 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:7436 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2025-46420 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2361963 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://gitlab.gnome.org/GNOME/libsoup/-/issues/438 (CNA: redhat)

- https://access.redhat.com/errata/RHSA-2025:4439 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:4440 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:4508 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:4538 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:4560 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:4568 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:4609 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:4624 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:7436 (secalert@redhat.com)

- https://access.redhat.com/security/cve/CVE-2025-46420 (secalert@redhat.com)

- https://bugzilla.redhat.com/show_bug.cgi?id=2361963 (secalert@redhat.com)

- https://gitlab.gnome.org/GNOME/libsoup/-/issues/438 (secalert@redhat.com)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2025-46420; retrieved 2026-11-05; source updated 2026-11-05

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-46420; retrieved 2026-11-05; source updated 2026-11-05

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2025-46420; retrieved 2026-11-05; source updated Not reported

Revision: 5ce4edfa29fb0a3e79c92d08729ae8a5e2f6e05d6ea9b963d5be42fbd5e46fc0

Canonical: https://y2.dev/cve/CVE-2025-46420

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