CVE-2026-12549

The fix for CVE-2026-2443 was regressed by a subsequent rework commit that replaced specific overflow checks with a general signed comparison. When a client sends a Range request with a suffix length exceeding the content size, the resulting negative start value is not properly clamped, leading to malformed HTTP 206 responses and log flooding.

CVSS v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-12549	Vendor Advisory Mitigation
https://access.redhat.com/security/cve/cve-2026-0716	Vendor Advisory Mitigation
https://bugzilla.redhat.com/show_bug.cgi?id=2489999	Issue Tracking Vendor Advisory
https://gitlab.gnome.org/GNOME/libsoup/-/work_items/516	Exploit Issue Tracking Patch Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:redhat:enterprise_linux:6.0:::::::*
	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:::::::*
	cpe:2.3:o:redhat:enterprise_linux:10.0:::::::*

Configuration 2 (hide)

cpe:2.3:a:gnome:libsoup:-:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-06-22 16:16

Updated : 2026-07-08 15:10

NVD link : CVE-2026-12549

Mitre link : CVE-2026-12549

CVE.ORG link : CVE-2026-12549

JSON object : View

Products Affected

redhat

enterprise_linux

gnome

libsoup

CWE

CWE-805

Buffer Access with Incorrect Length Value

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