CVE-2026-34479
Log4j1XmlLayout due to unescaped XML 1.0 forbidden characters vulnerability
Apache · Apache Log4j 1 to Log4j 2 bridge: Silent log event loss in Log4j1XmlLayout due to unescaped XML 1.0 forbidden characters
MSRC advisory April 30, 2026
Alert details
- Source feed
- Microsoft MSRC
- CVE ID
- CVE-2026-34479
- Affected products
- Apache Log4j 1 to Log4j 2 bridge: Silent log event loss in Log4j1XmlLayout due to unescaped XML 1.0 forbidden characters · Apache Apache Log4j 1 to Log4j 2 bridge: Silent log event loss in Log4j1XmlLayout due to unescaped XML 1.0 forbidden characters · Apache
What happened
Information published.
What it means for your business
Apache Apache Log4j 1 to Log4j 2 bridge: Silent log event loss in Log4j1XmlLayout due to unescaped XML 1.0 forbidden characters (CVE-2026-34479) was added to Microsoft’s security update guidance. Information published. PremierePC tracks MSRC advisories for Upstate SC businesses — patch or open a ticket if you need help verifying exposure.
Sources
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