CVE-2026-56859: Add recursion depth guard during decode in encoding/xml

highCVSS 7.5CVE-2026-56859

CSIRTS triage

vendor: Go product: encoding/xml Denial of service

What: The encoding/xml package lacks recursion depth guards during decoding, allowing denial of service via deeply nested XML.
Who is affected: Go applications that parse untrusted or user-supplied XML documents using encoding/xml.
Urgency: High severity (CVSS 7.5); unbounded XML nesting can cause stack overflow and crash; patch immediately.
Action: Update Go to a patched version that enforces recursion depth limits in encoding/xml decoding.

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: high — CVSS 7.5
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56859

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-2026-568590.57% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 44% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-56859	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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

Recent advisories for Add recursion depth

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

criticalCVE-2026-72194: In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: add depth limit …nvd · 2026-08-15