CVE-2026-58012: Glib: buffer over-read in g_regex_replace() via glib/gregex.c:string_append() and g_utf8_next_char()

mediumCVSS 6.5CVE-2026-58012

CSIRTS triage

vendor: Glib product: GlibOther

What: Buffer over-read can occur in g_regex_replace() due to certain function calls.
Who is affected: Users of Glib that utilize regex functionalities.
Urgency: This medium severity issue should be addressed to prevent potential data leaks.
Action: Update to the latest version of Glib.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: medium — CVSS 6.5
Published: 2026-06-09
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-58012

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-580120.32% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 24% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-58012	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

mediumCVE-2026-58012: A flaw was found in GLib. A buffer over-read can occur in the g_regex_replace function when us…nvd

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