CVE-2026-55555

HIGHNVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 0.4%, top 72% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.5Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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.

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
38(Track)
EG Risk 38/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity75% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
28%
KEV
Not listed

Published

July 22, 2026

Last Modified

August 5, 2026

Advisory Details (3)

Auto-updated Aug 5, 2026
Patch available. Sources: github, github_commit, github_release.
github Patch Available

File existence oracle via font-face stylesheet declaration · Advisory · dompdf/dompdf · GitHub

https://github.com/dompdf/dompdf/security/advisories/GHSA-7x2p-4jvh-6384
github_release Patch Available

Dompdf 3.1.6

Patch available: dompdf/dompdf v3.1.6

https://github.com/dompdf/dompdf/releases/tag/v3.1.6
github_commit Patch Available

commit 75c39a083bf7 (dompdf/dompdf)

Patch available: dompdf/dompdf v3.1.6 (contains commit 75c39a083bf7)

https://github.com/dompdf/dompdf/commit/75c39a083bf7298044fb27399b4cc183054438b4

Vendor Advisories for CVE-2026-55555(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(3 across 3 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
php-dompdf0.6.2+dfsg-3.1 ... 3.1.4+dfsg-2 (19 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
php-dompdf2.0.3+dfsg-1 ... 3.1.4+dfsg-2 (15 versions)——
Packagist(1)
PackageVulnerable rangeFixed inDependents
dompdf/dompdfv0.6.0 ... v3.1.5 (39 versions)3.1.6—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 12× in last 7d / 54× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-26 14:46 UTCEPSS rescore
  2. 2026-08-25 22:26 UTCEG score recompute
  3. 2026-08-25 13:49 UTCEPSS rescore
  4. 2026-08-24 22:19 UTCEG score recompute
  5. 2026-08-24 10:17 UTCEG score recompute
  6. 2026-08-23 10:05 UTCEG score recompute
  7. 2026-08-23 00:19 UTCEPSS rescore
  8. 2026-08-22 09:59 UTCEG score recompute
  9. 2026-08-21 23:49 UTCEPSS rescore
  10. 2026-08-21 09:52 UTCEG score recompute
  11. 2026-08-20 22:55 UTCEPSS rescore
  12. 2026-08-19 21:45 UTCEG score recompute
  13. 2026-08-19 17:04 UTCEPSS rescore
  14. 2026-08-18 20:55 UTCEG score recompute
  15. 2026-08-18 13:48 UTCEPSS rescore
  16. 2026-08-17 20:26 UTCEG score recompute
  17. 2026-08-17 13:47 UTCEPSS rescore
  18. 2026-08-16 17:44 UTCEG score recompute
  19. 2026-08-16 14:56 UTCEPSS rescore
  20. 2026-08-16 05:31 UTCEG score recompute
  21. 2026-08-16 02:14 UTCEPSS rescore
  22. 2026-08-15 05:26 UTCEG score recompute
  23. 2026-08-15 01:30 UTCEPSS rescore
  24. 2026-08-14 05:16 UTCEG score recompute
  25. 2026-08-13 22:00 UTCEPSS rescore
Show 31 more
  1. 2026-08-12 17:08 UTCEG score recompute
  2. 2026-08-12 13:51 UTCEPSS rescore
  3. 2026-08-11 17:02 UTCEG score recompute
  4. 2026-08-11 04:59 UTCEG score recompute
  5. 2026-08-11 00:00 UTCEPSS rescore
  6. 2026-08-09 16:52 UTCEG score recompute
  7. 2026-08-09 13:46 UTCEPSS rescore
  8. 2026-08-08 16:48 UTCEG score recompute
  9. 2026-08-08 16:37 UTCEPSS rescore
  10. 2026-08-07 16:43 UTCEG score recompute
  11. 2026-08-06 16:38 UTCEG score recompute
  12. 2026-08-06 13:47 UTCEPSS rescore
  13. 2026-08-06 04:35 UTCEG score recompute
  14. 2026-08-05 19:17 UTCEPSS rescore
  15. 2026-08-05 16:32 UTCEG score recompute▲ 5.20
  16. 2026-08-05 16:30 UTCNVD updateCVSS v3 → 7.5 · severity → HIGH
  17. 2026-08-05 09:58 UTCEG score recompute
  18. 2026-08-04 15:10 UTCEPSS rescore
  19. 2026-08-04 10:39 UTCEPSS rescore
  20. 2026-08-03 10:36 UTCEPSS rescore
  21. 2026-08-02 13:22 UTCEG score recompute
  22. 2026-08-02 02:27 UTCEPSS rescore
  23. 2026-08-01 04:16 UTCEPSS rescore
  24. 2026-07-30 16:47 UTCEG score recompute
  25. 2026-07-30 16:28 UTCEPSS rescore
  26. 2026-07-30 01:30 UTCEPSS rescore
  27. 2026-07-28 20:28 UTCEG score recompute
  28. 2026-07-28 19:29 UTCEG score recompute▲ 2.30
  29. 2026-07-28 19:27 UTCMITRE cvelistV5CVSS v3 → 2.3 · CVSS v4 → 2.3
  30. 2026-07-23 03:20 UTCEG score recompute
  31. 2026-07-22 21:20 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-55555?
CVE-2026-55555 is a high vulnerability published on July 22, 2026. 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…
When was CVE-2026-55555 disclosed?
CVE-2026-55555 was first published in the National Vulnerability Database on July 22, 2026, with the most recent update on August 5, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-55555 actively exploited?
CVE-2026-55555 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 71.9% of all scored CVEs.
What is the CVSS score of CVE-2026-55555?
CVE-2026-55555 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-55555?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-55555, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-55555

Explore →

Is Your Infrastructure Affected by CVE-2026-55555?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs