Skip to content
Fencer Vulns
medium 5.9

CVE-2026-15712 json

Soupclientmessageiohttp2: libsoup3: libsoup: http/2 goaway frame parsing heap buffer over-read via invalid nul-termination assumption

published 2026-07-14 3 mo ago modified 2026-11-06 2 d ago also EUVD-2026-44341

cvss
5.9
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 50%
public exploits
0
none known

Summary

A heap buffer over-read vulnerability was discovered in libsoup's (versions: libsoup 3.0 to 3.7.0) HTTP/2 connection tracking framework. When the library processes an HTTP/2 GOAWAY frame, it improperly handles the "Additional Debug Data" payload by assuming the data stream is a safely NUL-terminated C-string. Because the parser lacks strict length-boundary verification before reading this data, a remote, unauthenticated attacker can intentionally send a malformed GOAWAY frame missing the appropriate null delimiter. This causes the library to read past the end of the allocated buffer, triggering an application crash that results in a denial of service (DoS), or potentially exposing fragments of memory contents.

Patch / fix

  • libsoup SLES for SAP applications 16.0, SLES 16.0 3.6.6-160000.5.1
  • libsoup Linux Micro 6.0 3.4.2-159998.1.1
  • libsoup SLES for SAP 15 SP6, SLES 15 SP6-LTSS, SLE Module for Basesystem 15 SP7 3.4.4-150600.3.56.1
  • libsoup SLES for SAP 15 SP5, SLES for SAP 15 SP4, SLES 15 SP5-LTSS +5 more 3.0.4-150400.3.52.1

suse advisories SUSE-SU-2026:24470-1SUSE-SU-2026:24368-1SUSE-SU-2026:4558-1SUSE-SU-2026:4557-1

  • libsoup openSUSE Tumbleweed 3.8.1-1.1
  • libsoup openSUSE Leap 16.0 3.6.6-160000.5.1

opensuse advisories openSUSE-SU-2026:12365-1openSUSE-SU-2026:22181-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-15712 updated cvss 5.9

SoupClientMessageIOHTTP2: libsoup3: libsoup: HTTP/2 GOAWAY frame parsing heap buffer over-read via invalid NUL-termination assumption

  • Red Hat Enterprise Linux 10 libsoup3
    affected: workaround, no fix available “Fix deferred”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
3 mo ago

Exploit prediction

0.63% chance of exploitation in the next 30 days, higher than 50% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • gitlab.gnome.org https://gitlab.gnome.org/GNOME/libsoup/-/work_items/540 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

  • Red Hat Red Hat Enterprise Linux 10

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.