CVE-2026-45785

MEDIUMPre-NVD 6.26.2—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.2 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.1%, top 97% 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, secondary
Elevated
6.2
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 6.2Exploit: NoneExposed: 0

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

OpenMcdf is a fully .NET / C# library to manipulate Compound File Binary File Format files, also known as Structured Storage. In 3.1.3 and earlier, the BST name-lookup loop in DirectoryTree.TryGetDirectoryEntry (OpenMcdf/DirectoryTree.cs:35-46) walks directory entries by repeatedly calling directories.TryGetSibling(child, siblingType, validateColor). A crafted CFB file with cyclic Left/Right sibling links among directory entries, constructed so the per-step BST-order check in TryGetSibling (DirectoryEntries.cs:84-85) is satisfied at every step, drives this while (child is not null) loop forever. There is no cycle detection in TryGetDirectoryEntry, and the bug is reachable from RootStorage.OpenStorage(name), TryOpenStorage(name), OpenStream(name), and TryOpenStream(name), causing an unrecoverable denial of service. This issue is fixed in version 3.1.4.

CVSS v3
6.2
EG Score
6.2(medium)
EG Risk
44(Track)
EG Risk 44/100SSVC: 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
Severity62% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS
3.0%
KEV
Not listed

Published

May 19, 2026

Last Modified

July 21, 2026

Advisory Details (3)

Auto-updated Jul 17, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit, github_release, github.
github Patch Available🟡 PoC Available

Uncatchable infinite loop in DirectoryTree.TryGetDirectoryEntry on crafted CFB directory cycle · Advisory · openmcdf/openmcdf · GitHub

https://github.com/openmcdf/openmcdf/security/advisories/GHSA-5qwm-7pvp-w988
github_release Patch Available

v3.1.4

Patch available: openmcdf/openmcdf v3.1.4

https://github.com/openmcdf/openmcdf/releases/tag/v3.1.4
github_commit Patch Available

commit c6f82db722bd (openmcdf/openmcdf)

Patch available: openmcdf/openmcdf v3.1.4 (contains commit c6f82db722bd)

https://github.com/openmcdf/openmcdf/commit/c6f82db722bd85db7b0caed3ca1aa374f1e07bc7

Vendor Advisories for CVE-2026-45785(1)

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

Affected Packages

(1 across 1 ecosystem)
NuGet(1)
PackageVulnerable rangeFixed inDependents
OpenMcdf1.5.4 ... 3.1.3 (34 versions)3.1.4—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 7× 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. 2026-07-23 14:18 UTCEPSS rescore
  2. 2026-07-23 03:16 UTCEG score recompute
  3. 2026-07-22 14:08 UTCEPSS rescore
  4. 2026-07-21 15:24 UTCEPSS rescore
  5. 2026-07-20 17:08 UTCEPSS rescore
  6. 2026-07-19 14:31 UTCEPSS rescore
  7. 2026-07-19 02:29 UTCEPSS rescore
  8. 2026-06-14 23:18 UTCEPSS rescore
  9. 2026-06-13 23:00 UTCEPSS rescore
  10. 2026-06-12 23:12 UTCEPSS rescore
  11. 2026-05-24 06:13 UTCEG score recompute

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-45785?
CVE-2026-45785 is a medium vulnerability published on May 19, 2026. OpenMcdf is a fully .NET / C# library to manipulate Compound File Binary File Format files, also known as Structured Storage. In 3.1.3 and earlier, the BST name-lookup loop in DirectoryTree.TryGetDirectoryEntry (OpenMcdf/DirectoryTree.cs:35-46) walks directory entries by repeatedly calling…
When was CVE-2026-45785 disclosed?
CVE-2026-45785 was first published in the National Vulnerability Database on May 19, 2026, with the most recent update on July 21, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-45785 actively exploited?
CVE-2026-45785 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 3.0% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-45785?
CVE-2026-45785 has a CVSS v3 base score of 6.2 (NVD).
How do I remediate CVE-2026-45785?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-45785, 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

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