# CVE-2026-58010: GLib off-by-one error in GVariant serializer

Source: https://junglewise.ai/threats/cve-2026-58010-glib-off-by-one-error-in-gvariant-serializer  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-30. Updated: 2026-06-30  
License: CC BY 4.0 with a link back

CVE-2026-58010 · Severity: medium · CVSS 6.5 · Published 2026-06-30

GLib is a fundamental software library used by many Linux applications to handle data structures and communication. A flaw in how it processes certain data formats (GVariant) could allow an attacker to cause an application to crash or potentially leak a small amount of memory. This is particularly relevant for systems that process untrusted data from the network or via system communication buses like D-Bus.

Technologies: [Gnome Glib](https://junglewise.ai/threats/technologies/glib), [Red Hat Enterprise Linux 10](https://junglewise.ai/threats/technologies/enterprise-linux-10), [Red Hat Enterprise Linux 6](https://junglewise.ai/threats/technologies/enterprise-linux-6), [Red Hat Enterprise Linux 7](https://junglewise.ai/threats/technologies/enterprise-linux-7), [Red Hat Enterprise Linux 8](https://junglewise.ai/threats/technologies/enterprise-linux-8), [Red Hat Enterprise Linux 9](https://junglewise.ai/threats/technologies/enterprise-linux-9). Vendors: [Gnome](https://junglewise.ai/threats/vendors/gnome), [Red Hat](https://junglewise.ai/threats/vendors/red-hat).

## Quick answers

**Is CVE-2026-58010 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-58010 being exploited in the wild.

**How severe is CVE-2026-58010?** Medium severity, with a CVSS score of 6.5, published 30 June 2026.

**Which products and versions are affected?** GNOME GLib; Red Hat Red Hat Enterprise Linux 6; Red Hat Red Hat Enterprise Linux 7; Red Hat Red Hat Enterprise Linux 8; and 2 more.

**Is there a fix for CVE-2026-58010?** 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-2026-58010 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-58010?** Check whether you run Gnome Glib, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6 or one of the others listed. 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

An off-by-one error exists in the gvs_tuple_is_normal function within glib/gvariant-serialiser.c. During an alignment padding check, the code uses a '>' comparison instead of '>=' when validating offsets against the buffer size. This allows a 1-byte out-of-bounds read when the offset equals the value size. An attacker providing specially crafted GVariant data (e.g., via D-Bus or network protocols) can trigger this read. While the impact is primarily a 1-byte information disclosure, it can result in a denial of service (crash) if the out-of-bounds read crosses a memory page boundary. A fix involving a bounds check correction has been proposed.

## Affected products

- GNOME GLib
- Red Hat Red Hat Enterprise Linux 6
- Red Hat Red Hat Enterprise Linux 7
- Red Hat Red Hat Enterprise Linux 8
- Red Hat Red Hat Enterprise Linux 9
- Red Hat Red Hat Enterprise Linux 10

## Timeline

- 2026-01-29: disclosed: Initial report via YesWeHack
- 2026-06-30: advisory: CVE published by Red Hat and NVD

## References

- [https://access.redhat.com/downloads/content/package-browser/](https://access.redhat.com/downloads/content/package-browser/)
- [https://access.redhat.com/security/cve/CVE-2026-58010](https://access.redhat.com/security/cve/CVE-2026-58010)
- [https://bugzilla.redhat.com/show_bug.cgi?id=2492243](https://bugzilla.redhat.com/show_bug.cgi?id=2492243)
- [https://gitlab.gnome.org/GNOME/glib/-/issues/3915](https://gitlab.gnome.org/GNOME/glib/-/issues/3915)

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