CVE-2026-55555: Dompdf: File existence oracle via font-face stylesheet declaration
Affected: dompdf · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 43% of scored CVEs
DescriptionCVE.org
Dompdf is an HTML to PDF converter for PHP. Versions 3.15 and prior are vulnerable to a File Existence Oracle attack through the manipulation of the CSS @font-face directive. By providing malicious HTML that references local files via the file:// protocol repeatedly, an attacker can trigger PHP memory exhaustion. Because Dompdf behaves differently depending on whether a referenced local file exists (an existing file is processed repeatedly until it triggers an "Allowed memory size exhausted" crash, whereas a missing file fails fast or is ignored and never hits the memory limit), an attacker can use this observable discrepancy as an oracle to enumerate sensitive files on the server regardless of CHROOT restrictions. Exploitation requires the attacker to supply unrestricted or unsanitized HTML in a request that permits large data, plus a configuration where Dompdf's memory limit is low enough to be exhausted (with $_dompdf_show_warnings=true making the overflow easier to reach). This issue has been fixed in version 3.16.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- dompdf · dompdf< 3.1.6
On the Atlas
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CoverageNo articles yet
No CyberSIXT article names CVE-2026-55555 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.