How severe is CVE-2026-58013?

CVE-2026-58013 has a CVSS score of 6.5/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2026-58013?

Affected package information for CVE-2026-58013 is not yet fully mapped. Check the official advisory links for details.

How do I fix CVE-2026-58013?

Upgrade the affected component to the fixed release for CVE-2026-58013, or apply your distribution's backported patch — distro builds are often patched at an older version number, so check your vendor's advisory rather than the upstream version alone.

How do I detect CVE-2026-58013 in my code and dependencies?

Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).

How do I mitigate CVE-2026-58013 if there is no patch (or I can't update yet)?

Constrain what reaches the vulnerable code: limit the size and shape of untrusted input, isolate the affected component in a sandboxed or least-privileged process, and enable the platform's memory-safety mitigations (ASLR, stack protector, hardened allocator) so an out-of-bounds access is more likely to fail closed than to be exploitable.

Is CVE-2026-58013 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-58013 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-58013?

CVE-2026-58013 has an EPSS (Exploit Prediction Scoring System) score of 0.9%, placing it in the 57th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-58013?

CVE-2026-58013 is classified as CWE-126 (CWE-126). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-58013 published, and has it been updated?

CVE-2026-58013 was published on June 30, 2026 and was last updated on October 1, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🛡️

Not in CISA KEV

MEDIUM severity

CVE-2026-58013 — glib

MEDIUM

CVE-2026-58013 is a medium-severity (CVSS 6.5) CWE-126 vulnerability. A fix is available — see the affected versions and patch details below.

Glib: buffer over-read in glib/giochannel.c via "g_io_channel_read_line_backend"

Published

Jun 30, 2026

Updated

Oct 1, 2026

Affected

2 products

Patched

See advisory

Exploits

None indexed

Exploitation data as of Oct 1, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-58013.

EPSS Exploitation Probability

via FIRST.org ↗

0.9%probability of exploitation in next 30 days

Lower Risk+0.38%

Lower risk than most CVEs57th percentile — riskier than 57% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2026-58013 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 381,682 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Description

A flaw was found in GLib. A buffer over-read can occur in g_io_channel_read_line_backend() in the giochannel.c file when a custom line terminator with a length greater than one is set, causing memcmp to read past the GString buffer. This vulnerability can cause a minor information disclosure of 7 bytes or a denial of service when the buffer over-read crosses a page boundary.

Affected Products

2 products · 6 configurations

Application

glibgnome

< 2.88.1

range

enterprise linuxredhat

5 versions

6.07.08.09.010.0

Detection & mitigation playbook

Vulnerability

Detect
Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).
Fix
Upgrade the affected component to the fixed release for CVE-2026-58013, or apply your distribution's backported patch — distro builds are often patched at an older version number, so check your vendor's advisory rather than the upstream version alone.
Workarounds
Constrain what reaches the vulnerable code: limit the size and shape of untrusted input, isolate the affected component in a sandboxed or least-privileged process, and enable the platform's memory-safety mitigations (ASLR, stack protector, hardened allocator) so an out-of-bounds access is more likely to fail closed than to be exploitable.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

Any applications calling g_io_channel_set_line_term() with a multi-byte line terminator (length greater than one) and subsequently calling g_io_channel_read_line_backend() are vulnerable to this issue. This flaw can cause a buffer over-read of 8 bytes, leading to an information disclosure of 7 bytes or a denial of…

Workaround published by Red Hat

To mitigate this vulnerability, restrict any custom line terminator string passed to g_io_channel_set_line_term() to a maximum length of one byte before calling g_io_channel_read_line_backend(). Using the default line terminators will completely neutralize this issue.

Source: Red Hat security advisory for CVE-2026-58013 (CC BY 4.0)

Product	Fixed in	Advisory
Red Hat Enterprise Linux 10	`glib2-0:2.80.4-12.el10_2.21`	RHSA-2026:57015
Red Hat Enterprise Linux 10.0 Extended Update Support	`glib2-0:2.80.4-4.el10_0.17`	RHSA-2026:65767
Red Hat Enterprise Linux 7 Extended Lifecycle Support	`glib2-0:2.56.1-13.el7_9.1`	RHSA-2026:65773
Red Hat Enterprise Linux 8	`mingw-glib2-0:2.70.1-9.el8_10`	RHSA-2026:49512
Red Hat Enterprise Linux 8	`glib2-0:2.56.4-177.el8_10`	RHSA-2026:61766
Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support	`glib2-0:2.56.4-10.el8_4.7`	RHSA-2026:65762
Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support	`glib2-0:2.56.4-158.el8_6.7`	RHSA-2026:65769
Red Hat Enterprise Linux 8.8 Telecommunications Update Service	`glib2-0:2.56.4-165.el8_8.2`	RHSA-2026:65771

Frequently Asked Questions

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