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Red HatCVE-2026-66337

Red Hat libsoup. An unsigned integer underflow: integer overflow

Medium6.5CVE-2026-66337 · Published Jul 24, 2026 · updated Aug 24, 2026

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.

Red Hat advisory

Affected versions

PackageAffectedFixed in
Red Hat Enterprise Linux 10
Product
all versionsNo fix yet
Red Hat Enterprise Linux 6
Product
all versionsNo fix yet
Red Hat Enterprise Linux 7
Product
all versionsNo fix yet
Red Hat Enterprise Linux 8
Product
all versionsNo fix yet
Red Hat Enterprise Linux 9
Product
all versionsNo fix yet
Details and references
CVSS 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
Severity from
the vendor (its own CVE record or advisory)
Weakness
CWE-125

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