Fireshare facilitates self-hosted media and link sharing. In version 1.5.1, an authenticated path traversal vulnerability in Fireshare’s chunked upload endpoint allows an attacker to write arbitrary files outside the intended upload directory. The checkSum multipart field is used directly in filesystem path construction without sanitization or containment checks. This enables unauthorized file writes to attacker-chosen paths writable by the Fireshare process (e.g., container /tmp), violating integrity and potentially enabling follow-on attacks depending on deployment. Version 1.5.2 fixes the issue.
CVE-2026-33645
HIGHNVD 8.18.1
EchelonGraph scoreLOW confidence
This high-severity CVE scores 8.1 under NVD CVSS v3. EPSS exploit-prediction score not yet available (the EPSS model rescores nightly; freshly-published CVEs typically appear within 48 hours). 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: nvd
8.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: —CVSS: 8.1Exploit: None knownExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 8.1
- EG Score
- 8.1(low)
- EG Risk
- 41(Track)EG Risk 41/100SSVC: 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 computedSeverity81% × 45%Exploitation0% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- —
- EPSS %ILE
- —
- KEV
- Not listed
Published
March 26, 2026
Last Modified
June 17, 2026
References (3)
- security-advisories@githubhttps://github.com/ShaneIsrael/fireshare/releases/tag/v1.5.2
- security-advisories@githubhttps://github.com/ShaneIsrael/fireshare/security/advisories/GHSA-7q8r-vpq3-89m7
- 134c704f-9b21-4f2e-91b3-4a467353bcc0https://github.com/ShaneIsrael/fireshare/security/advisories/GHSA-7q8r-vpq3-89m7
Weakness Classification(2)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 1× in last 7d / 1× 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.
- 2026-07-27 14:21 UTCEG score recompute
Related CVEs(same CWE)
Frequently asked(4)
What is CVE-2026-33645?
CVE-2026-33645 is a high vulnerability published on March 26, 2026. Fireshare facilitates self-hosted media and link sharing. In version 1.5.1, an authenticated path traversal vulnerability in Fireshare’s chunked upload endpoint allows an attacker to write arbitrary files outside the intended upload directory. The checkSum multipart field is used directly in…
When was CVE-2026-33645 disclosed?
CVE-2026-33645 was first published in the National Vulnerability Database on March 26, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
What is the CVSS score of CVE-2026-33645?
CVE-2026-33645 has a CVSS v3 base score of 8.1 (NVD). The EG score is currently aggregating — additional source signals are being incorporated as they become available..
How do I remediate CVE-2026-33645?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-33645, 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
Explore the affected products and dependency analysis for CVE-2026-33645
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