Description
A flaw was found in libsoup. When max-incoming-payload-size is unlimited (0), SoupWebsocketConnection could grow its incoming GByteArray based on an attacker-controlled frame length until the length wrapped, causing a heap buffer overflow while reading frame data.
Published: 2026-09-29
Score: 8.6 High
EPSS: < 1% Very Low
KEV: No
Impact: Heap buffer overflow in Libsoup
Action: Apply Workaround
AI Analysis

Impact

A flaw in Libsoup allows an attacker controlling the frame length to force the SoupWebsocketConnection to grow its incoming GByteArray until the length value wraps, causing a heap buffer overflow while reading frame data. This can enable arbitrary code execution or a denial‑of‑service condition. The weakness, identified as CWE-125, is a heap buffer overflow.

Affected Systems

Red Hat Enterprise Linux 6 through 10, including 6, 7, 8, 9, and 10 distributions. All versions using the Libsoup component are affected.

Risk and Exploitability

The CVSS score of 8.6 indicates high severity, but the EPSS score is not available and the vulnerability is not listed in the CISA KEV catalog. Exploitation would likely require network access to a WebSocket endpoint that accepts arbitrary frame lengths and has an unlimited max‑incoming‑payload‑size. The vendor workaround suggests limiting the payload size and restricting exposure to trusted peers, reducing risk but not eliminating it until the issue is resolved.

Generated by OpenCVE AI on September 30, 2026 at 00:38 UTC.

Remediation

Vendor Workaround

To mitigate this configure a finite max-incoming-payload-size (do not set it to 0/unlimited) on SoupWebsocketConnection. Restrict WebSocket exposure to trusted peers.


OpenCVE Recommended Actions

  • Configure a finite max‑incoming‑payload‑size on SoupWebsocketConnection to prevent unlimited buffer growth.
  • Restrict WebSocket exposure to trusted peers or disable unused WebSocket services.
  • Monitor the vendor’s remediation status and apply any available patch or update that addresses the heap buffer overflow in Libsoup.

Generated by OpenCVE AI on September 30, 2026 at 00:38 UTC.

Tracking

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Advisories
Source ID Title
Ubuntu USN Ubuntu USN USN-8975-1 libsoup vulnerabilities
History

Wed, 04 Nov 2026 22:00:00 +0000

Type Values Removed Values Added
CPEs cpe:/o:redhat:enterprise_linux:6 cpe:/o:redhat:rhel_els:6

Mon, 02 Nov 2026 13:00:00 +0000

Type Values Removed Values Added
CPEs cpe:/a:redhat:rhel_aus:8.6::appstream
cpe:/a:redhat:rhel_eus_long_life:8.6::appstream
cpe:/o:redhat:rhel_aus:8.6::baseos
cpe:/o:redhat:rhel_eus_long_life:8.6::baseos
References

Mon, 02 Nov 2026 09:15:00 +0000

Type Values Removed Values Added
First Time appeared Redhat enterprise Linux Eus
CPEs cpe:/o:redhat:enterprise_linux_eus:10.0
Vendors & Products Redhat enterprise Linux Eus
References

Mon, 02 Nov 2026 05:30:00 +0000

Type Values Removed Values Added
First Time appeared Redhat rhel Els
Redhat rhel Eus
CPEs cpe:/o:redhat:enterprise_linux:7 cpe:/a:redhat:rhel_eus:9.6::appstream
cpe:/o:redhat:rhel_els:7
Vendors & Products Redhat rhel Els
Redhat rhel Eus
References

Mon, 02 Nov 2026 03:45:00 +0000

Type Values Removed Values Added
First Time appeared Redhat rhel Tus
CPEs cpe:/a:redhat:rhel_e4s:8.8::appstream
cpe:/a:redhat:rhel_tus:8.8::appstream
cpe:/o:redhat:rhel_e4s:8.8::baseos
cpe:/o:redhat:rhel_tus:8.8::baseos
Vendors & Products Redhat rhel Tus
References

Mon, 02 Nov 2026 02:45:00 +0000

Type Values Removed Values Added
First Time appeared Redhat rhel E4s
CPEs cpe:/a:redhat:rhel_e4s:9.2::appstream
cpe:/a:redhat:rhel_e4s:9.4::appstream
Vendors & Products Redhat rhel E4s
References

Thu, 29 Oct 2026 19:45:00 +0000

Type Values Removed Values Added
First Time appeared Redhat rhel Aus
Redhat rhel Eus Long Life
CPEs cpe:/a:redhat:rhel_aus:8.4::appstream
cpe:/a:redhat:rhel_eus_long_life:8.4::appstream
cpe:/o:redhat:rhel_aus:8.4::baseos
cpe:/o:redhat:rhel_eus_long_life:8.4::baseos
Vendors & Products Redhat rhel Aus
Redhat rhel Eus Long Life
References

Mon, 19 Oct 2026 04:30:00 +0000

Type Values Removed Values Added
CPEs cpe:/o:redhat:enterprise_linux:8 cpe:/a:redhat:enterprise_linux:8::appstream
cpe:/o:redhat:enterprise_linux:8::baseos
References

Thu, 15 Oct 2026 17:00:00 +0000

Type Values Removed Values Added
CPEs cpe:/o:redhat:enterprise_linux:10 cpe:/o:redhat:enterprise_linux:10.2
References

Thu, 15 Oct 2026 13:30:00 +0000

Type Values Removed Values Added
First Time appeared Gnome
Gnome libsoup
CPEs cpe:2.3:a:gnome:libsoup:*:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*
Vendors & Products Gnome
Gnome libsoup

Thu, 15 Oct 2026 05:30:00 +0000

Type Values Removed Values Added
CPEs cpe:/o:redhat:enterprise_linux:9 cpe:/a:redhat:enterprise_linux:9::appstream
References

Wed, 30 Sep 2026 21:00:00 +0000

Type Values Removed Values Added
First Time appeared Libsoup
Libsoup libsoup
Vendors & Products Libsoup
Libsoup libsoup

Wed, 30 Sep 2026 20:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 29 Sep 2026 17:30:00 +0000

Type Values Removed Values Added
Description A flaw was found in libsoup. When max-incoming-payload-size is unlimited (0), SoupWebsocketConnection could grow its incoming GByteArray based on an attacker-controlled frame length until the length wrapped, causing a heap buffer overflow while reading frame data.
Title Libsoup: libsoup: heap buffer overflow during websocket receive-buffer growth
First Time appeared Redhat
Redhat enterprise Linux
Weaknesses CWE-125
CPEs cpe:/o:redhat:enterprise_linux:10
cpe:/o:redhat:enterprise_linux:6
cpe:/o:redhat:enterprise_linux:7
cpe:/o:redhat:enterprise_linux:8
cpe:/o:redhat:enterprise_linux:9
Vendors & Products Redhat
Redhat enterprise Linux
References
Metrics cvssV3_1

{'score': 8.6, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H'}


Subscriptions

Gnome Libsoup
Libsoup Libsoup
Redhat Enterprise Linux Enterprise Linux Eus Rhel Aus Rhel E4s Rhel Els Rhel Eus Rhel Eus Long Life Rhel Tus
cve-icon MITRE

Status: PUBLISHED

Assigner: redhat

Published:

Updated: 2026-11-04T21:44:30.719Z

Reserved: 2026-09-29T13:19:17.913Z

Link: CVE-2026-102558

cve-icon Vulnrichment

Updated: 2026-09-30T19:00:05.013Z

cve-icon NVD

Status : Modified

Published: 2026-09-29T18:17:08.340

Modified: 2026-11-04T22:17:43.783

Link: CVE-2026-102558

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-30T20:40:34Z

Weaknesses