Quick answers
- Is CVE-2026-15712 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-15712 being exploited in the wild.
- How severe is CVE-2026-15712?
- Medium severity, with a CVSS score of 5.9, published 14 July 2026.
- Which products and versions are affected?
- Gnome Libsoup 3.0 to 3.7.0.
- Is there a fix for CVE-2026-15712?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-15712 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-15712?
- Check whether you run Gnome Libsoup at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A heap buffer over-read exists in libsoup (versions 3.0 through 3.7.0) within the `on_frame_recv_callback()` function of the HTTP/2 backend (`soup-client-message-io-http2.c`). The vulnerability occurs when the library processes an HTTP/2 GOAWAY frame containing 'Additional Debug Data'. The parser passes this data to `h2_debug()` using a `%s` format string, which assumes a NUL-terminated C-string. However, the underlying `nghttp2` library allocates this buffer without a NUL terminator. An unauthenticated remote attacker can send a malformed GOAWAY frame to trigger an out-of-bounds read. This typically results in a denial of service (application crash) or potential information disclosure, though the over-read is only triggered when debug logging is enabled (e.g., `G_MESSAGES_DEBUG=libsoup-http2`).
Affected products
- GNOME libsoup 3.0 to 3.7.0
- Red Hat Red Hat Enterprise Linux 10 affected
Timeline
- 2026-02-13: disclosed: Initial report via YesWeHack
- 2026-07-14: advisory: CVE published and NVD record created