# CVE-2025-11021: Libsoup: out-of-bounds read in cookie date handling of libsoup http library

Status: published. Published: 2025-09-26. Updated: 2026-11-04.

A flaw was found in the cookie date handling logic of the libsoup HTTP library, widely used by GNOME and other applications for web communication. When processing cookies with specially crafted expiration dates, the library may perform an out-of-bounds memory read. This flaw could result in unintended disclosure of memory contents, potentially exposing sensitive information from the process using libsoup.

## Remediation

- workaround: Mitigation for this issue is either not available or the currently available options don’t meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to a widespread installation base, or stability. It is strongly recommended to apply vendor-supplied patches once available. (source: CNA: redhat)

## Affected products and versions

-  /  (libsoup): ≥ 0; ≤ 3.6.5 (affected, semver). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 10 (libsoup3): ≥ 0:3.6.5-3.el10_0.7; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 10 (libsoup3): ≥ 0:3.6.5-3.el10_1.6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 Extended Lifecycle Support (libsoup): ≥ 0:2.62.2-9.el7_9; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (libsoup): ≥ 0:2.62.3-10.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_2.6; < * (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_4.6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On (libsoup): ≥ 0:2.62.3-2.el8_4.6; < * (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_6.6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Telecommunications Update Service (libsoup): ≥ 0:2.62.3-2.el8_6.6; < * (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_6.6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions (libsoup): ≥ 0:2.62.3-3.el8_8.6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (libsoup): ≥ 0:2.72.0-10.el9_6.3; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (libsoup): ≥ 0:2.72.0-12.el9_7.1; < * (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_0.6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions (libsoup): ≥ 0:2.72.0-8.el9_2.6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.4 Extended Update Support (libsoup): ≥ 0:2.72.0-8.el9_4.6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 6 (libsoup): Version range not reported. Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N; source: CNA: redhat

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N; source: NVD: secalert@redhat.com

- CISA KEV: No listing in collected sources

- EPSS: 0.64% as of 2026-11-04; percentile 50.63%

- SSVC: exploitation none; automatable yes; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-125

## Exploit evidence

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

## References

- https://access.redhat.com/errata/RHSA-2025:18183 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:19713 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:19714 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:20959 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:21032 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:21655 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:21656 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:21657 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:21664 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:21665 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:21666 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:21772 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2025:22013 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2025-11021 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2399627 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://gitlab.gnome.org/GNOME/libsoup/-/issues/459 (CNA: redhat)

- https://access.redhat.com/errata/RHSA-2025:18183 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:19713 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:19714 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:20959 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:21032 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:21655 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:21656 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:21657 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:21664 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:21665 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:21666 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:21772 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2025:22013 (secalert@redhat.com)

- https://access.redhat.com/security/cve/CVE-2025-11021 (secalert@redhat.com)

- https://bugzilla.redhat.com/show_bug.cgi?id=2399627 (secalert@redhat.com)

- https://gitlab.gnome.org/GNOME/libsoup/-/issues/459 (secalert@redhat.com)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2025-11021; retrieved 2026-11-04; source updated 2026-11-04

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-11021; retrieved 2026-11-05; source updated 2026-11-04

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2025-11021; retrieved 2026-11-04; source updated Not reported

Revision: 65004407cfffddc12a3dd24e878a0f7d1656c620b76533fc11d943347e6592fd

Canonical: https://y2.dev/cve/CVE-2025-11021

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