CVE-2026-55555
Dompdf: File existence oracle via font-face stylesheet declaration
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 4.0 | Low2.3 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N |
| NVDNVD · Analyzed | 4.0 | Low2.3 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 0.51% · top 56% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Low 2.3.
Weakness
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Packagistdompdf/dompdfGHSA-7x2p-4jvh-6384 (opens in a new tab)
References (3)
- https://github.com/dompdf/dompdf/security/advisories/GHSA-7x2p-4jvh-6384 (opens in a new tab)x_refsource_CONFIRMexploit
- https://github.com/dompdf/dompdf/commit/75c39a083bf7298044fb27399b4cc183054438b4 (opens in a new tab)x_refsource_MISC
- https://github.com/dompdf/dompdf/releases/tag/v3.1.6 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-7x2p-4jvh-6384 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-55555)Record last updated .