DOMPurify before 3.4.16 contains a cross-site scripting vulnerability that allows attackers to bypass sanitization because IN_PLACE mode returns a force-removed style element whose text content still carries markup. Attackers can supply a style element containing a closing style tag and an img onerror payload, which executes script when the application serializes and re-parses the returned node.
CVE-2026-109345
MEDIUMPre-NVD 6.16.1Trending — 4 sources updated this weekElevatedEG-KEV Tier 3: ElevatedEG-KEV is EchelonGraph's own tiering of exploitation signals from CISA KEV, CISA's SSVC data (Vulnrichment), ransomware data, public exploit-code references and EPSS.Tier 3 is not evidence of exploitation. It means public exploit code is referenced, or CISA's SSVC data says "public PoC", or EPSS ranks the CVE in the top 5%.Signals for this CVE: CISA's SSVC exploitation value: public PoC.EchelonGraph confidence 38%: a heuristic from the tier and the number of signals, not a measured probability.
EchelonGraph scoreHIGH confidence
“—” beside the score: it is equal to the CVSS score beside it.
Score 6.1 from GitHub Security Advisory published 2026-10-12. A secondary CVSS source baseline 6.1; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, a secondary CVSS source
6.1EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (the SSVC decision on this page).
- CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS: 6.1Exploit: No code on recordExposed services: Not assessed
A fix is available — apply it.
- CVSS v3
- 6.1
- EG Score
- 6.1MEDIUMhigh confidence
- EG Risk
- 43EG Risk 43/100
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 (value × EchelonGraph’s weight)Severity61% × 45%The EG Score, 6.1 of 10.Exploitation40% × 40%EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.Automatability0% × 15%CISA's SSVC Automatable value: no (Vulnrichment).SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.Action: A fix is available. Apply it within your standard update timelines. - EPSS PROB
- 0.2%
- EPSS %ILE
- 9th
- KEV
- Not listed
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines.
Exploitation public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it
Published
October 12, 2026
Last Modified
October 13, 2026
References (2)
- disclosure@vulncheck · CISA-ADPhttps://github.com/cure53/DOMPurify/security/advisories/GHSA-6688-9rhm-gjv2Vendor Advisory · Exploit
- disclosure@vulncheckhttps://www.vulncheck.com/advisories/dompurify-before-3.4.16-xss-via-in-place-returned-rawtext-rootThird Party Advisory
Vendor Advisories for CVE-2026-109345(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)
npm(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| dompurify | — |
| — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 8× in last 7d / 8× in last 30d)
Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.
- 2026-10-13 18:27 UTCEG score recompute
- 2026-10-13 18:27 UTCGHSA enrichmentGHSA-cjhx-p48c-gfm9 · GitHub CVSS 6.1
- 2026-10-13 17:52 UTCEG score recompute
- 2026-10-13 17:52 UTCGHSA enrichmentGHSA-cjhx-p48c-gfm9 · GitHub CVSS 6.1
- 2026-10-13 16:33 UTCEPSS rescoreEPSS 0.2% · 9th percentile
- 2026-10-12 17:27 UTCEG score recompute
- 2026-10-12 16:26 UTCEG score recomputeFirst assessed: 6.1 MEDIUM
- 2026-10-12 16:25 UTCMITRE cvelistV5first tracked
Related CVEs(same product + same CWE)
Same product
10 shownnpm:dompurify
Frequently asked(5)
What is CVE-2026-109345?
CVE-2026-109345 is a medium-severity vulnerability; its CVE record was published on October 12, 2026. DOMPurify before 3.4.16 contains a cross-site scripting vulnerability that allows attackers to bypass sanitization because IN_PLACE mode returns a force-removed style element whose text content still carries markup. Attackers can supply a style element containing a closing style tag and an img…
When was CVE-2026-109345 made public?
CVE-2026-109345 was made public on September 23, 2026: that is the date its CVE record's CNA, VulnCheck, gives for when the vulnerability was made public. The CVE record itself was published on October 12, 2026. EchelonGraph's copy of the record carries a last-modified date of October 13, 2026; the record at its source may have been updated since.
Is CVE-2026-109345 actively exploited?
CVE-2026-109345 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (9th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-109345?
CVE-2026-109345 has a CVSS base score of 6.1 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-109345?
A fix for CVE-2026-109345 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-109345 are linked in the Vendor Advisories panel on this page.
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-109345
Is Your Infrastructure Affected by CVE-2026-109345?
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