Description
A flaw was found in libsoup. An unsigned integer underflow in the soup_filter_input_stream_read_until() function causes a heap buffer over-read when parsing multipart HTTP responses. A malicious HTTP server can exploit this by sending a crafted multipart response, potentially causing the client application to crash or disclose sensitive heap memory.
Affected products
gnome: libsoup; redhat: enterprise linux
References2
- access.redhat.com/security/cve/CVE-2026-66337 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2506949 ExploitIssue TrackingVendor Advisory
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L - EPSS — exploit probability
- 0% percentile: 16 · as of 14 November 2026
- CWE
- CWE-125
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.