GLib: Buffer Over-read
CVE-2026-58012 is a high-severity buffer over-read vulnerability in GLib from GNOME, with a CVSS 3.1 base score of 8.2 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 2.86.5, 2.88.1 as the first without the flaw, so updating GLib to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.49% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update GLib to 2.86.5 or 2.88.1, whichever matches your release line, or a later version.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
Version data comes from the organisation that assigned the CVE; 7 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- LowSome restricted data can be read.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 6.5 | Medium | CNA (redhat.com) |
| CVSS 3.1 | 8.2 | High | NVD |
Official description
A flaw was found in GLib. A buffer over-read can occur in the g_regex_replace function when used with the `G_REGEX_RAW` compile flag and case-change replacement escapes because the string_append function processes matched substrings using UTF-8 functions that assume valid UTF-8 input, even when the string is treated as raw bytes. This vulnerability can cause a minor information disclosure of 1-5 bytes and a denial of service when the buffer over-read crosses a page boundary.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Buffer Over-read
The product reads from a buffer using buffer access mechanisms such as indexes or pointers that reference memory locations after the targeted buffer.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Other references
- access.redhat.com/errata/RHSA-2026:49512
- access.redhat.com/errata/RHSA-2026:55440
- access.redhat.com/errata/RHSA-2026:57015
- access.redhat.com/errata/RHSA-2026:58981
- access.redhat.com/errata/RHSA-2026:61766
- access.redhat.com/errata/RHSA-2026:61783
- access.redhat.com/errata/RHSA-2026:63135
- access.redhat.com/errata/RHSA-2026:63138
- access.redhat.com/errata/RHSA-2026:63140
- access.redhat.com/errata/RHSA-2026:65762
- access.redhat.com/errata/RHSA-2026:65763
- access.redhat.com/errata/RHSA-2026:65767
- access.redhat.com/errata/RHSA-2026:65768
- access.redhat.com/errata/RHSA-2026:65769
- access.redhat.com/errata/RHSA-2026:65770
Other vulnerabilities in GLib
- 9.1 Critical severity
- 7.5 High severity
- 8.6 High severity
- 8.2 High severity
- 7.5 High severity
- 8.2 High severity
Recent Buffer Over-read vulnerabilities
- 7.5 High severity
- 7.3 High severity
- 8.2 High severity
- 8.2 High severity
- 7.5 High severity
- 7.1 High severity
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