libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_GetBuffer, XML_Parse, XML_ParseBuffer, XML_ParserFree, or XML_ParserReset from within handlers in cases of a policy violation. Thus, a use-after-free can occur,
CVE-2026-50219
“—” beside the score: it is equal to NVD's CVSS score.
This medium-severity CVE scores 5.9 under NVD CVSS v3. EPSS exploit probability: 0.2% (7th percentile of EPSS-scored CVEs). GitHub Security Advisory CVSS 4.9 is lower than this score; a lower GitHub score revises it only when its advisory is newer than the CVE record's last change, and this advisory (published 2026-06-04) is not newer than that change (2026-07-22), so it does not.
Also known asEUVD-2026-34206 (ENISA EUVD) · GHSA-v3cw-2f3g-f38x (GitHub Security Advisories)Source: ENISA EUVD
- Lower severity and no public exploit yet
A fix is available — apply it.
- CVSS v3
- 5.9
- EG Score
- 5.9MEDIUMmedium confidence
- EG Risk
- 27EG Risk 27/100
EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.
How it’s computed (value × EchelonGraph’s weight)Severity59% × 45%Impact severity (EG Severity): CVSS 5.9 of 10. Never the KEV-floored or EPSS-lifted EG Score.Exploitation0.2% × 40%FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.Automatability0% × 15%CISA's SSVC Automatable value: no (Vulnrichment).SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.Exploitation none (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
- 7th
- KEV
- Not listed
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (5.9): severity, escalated by confirmed exploitation. This CVE's 5.9 is its impact severity (EG Severity), not escalated.
- EG Severity
- 5.9 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.NVD CVSS v3 · CVSS v3.0 or v3.1
- EG Likelihood
- 0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-24). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.
A fix is available. Apply it within your standard update timelines.
Exploitation none (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
June 4, 2026
Last Modified
July 22, 2026
Advisory Details (1)
Auto-updated Jun 14, 2026[CVE-2026-50219] Introduce handler call depth tracking
Fix merged in libexpat/libexpat PR #1246 on 2026-06-04 — awaiting tagged release
https://github.com/libexpat/libexpat/pull/1246Vendor Advisories for CVE-2026-50219(8)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
- RHSA-2026:79357Red Hat Product SecurityHigh
Red Hat Security Advisory: Red Hat Cost Management On-Premise container image update
- RHSA-2026:67956Red Hat Product SecurityHigh
Red Hat Security Advisory: Red Hat Update Infrastructure 5.3 security update
- RHSA-2026:64812Red Hat Product SecurityMedium
Red Hat Security Advisory: expat security update
- RHSA-2026:64810Red Hat Product SecurityMedium
Red Hat Security Advisory: expat security update
- RHSA-2026:64809Red Hat Product SecurityMedium
Red Hat Security Advisory: expat security update
- RHSA-2026:30647Red Hat Product SecurityMedium
Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update
- CVE-2026-50219Microsoft Security Response Center (MSRC)Low
libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_GetBuffer, XML_Parse, XML_ParseBuffer, XML_ParserFree, or XML_ParserReset from within handlers in cases of a policy violation. Thus, a use-after-free can occur,
- GHSA-v3cw-2f3g-f38xGitHub Security AdvisoriesMedium
libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_GetBuffer, XML_Parse,...
Patch Availability(5)
| Vendor / Ecosystem | Fix (by version range) / Patch | Released | Source |
|---|---|---|---|
| ubuntu | libexpat1-dev (2.1.0-4ubuntu1.4+esm12) @ trusty | 2026-10-22 | ubuntu |
| redhat | expat-0:2.7.3-1.el10_2.3 | 2026-09-08 | redhat |
| redhat | expat-0:2.5.0-2.el8_10.2 | 2026-09-08 | redhat |
| redhat | expat-0:2.5.0-6.el9_8.3 | 2026-09-08 | redhat |
| redhat | expat-main-2.8.2-1.hum1 | 2026-06-28 | redhat |
Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.
Affected Packages
(8 across 8 ecosystems)
Alpine:v3.21(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| expat | — |
| — |
Alpine:v3.22(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| expat | — |
| — |
Alpine:v3.23(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| expat | — |
| — |
Alpine:v3.24(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| expat | — |
| — |
Debian:11(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| expat | 2.2.10-2 ... 2.8.2-1~deb13u1 (47 versions) |
| — |
Debian:12(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| expat | 2.5.0-1, 2.5.0-1+deb12u1, 2.5.0-1+deb12u2 |
| — |
Debian:13(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| expat | 2.7.1-2 ... 2.8.1-1 (9 versions) |
| — |
Debian:14(1)
| Package | Vulnerable range | Fix by version range | Dependents |
|---|---|---|---|
| expat | 2.7.1-2 ... 2.8.2-1~deb13u1 (10 versions) |
| — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Additional Vendor Advisories
(1)
Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.
Data Freshness Timeline
(refreshed 11× in last 7d / 39× 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.
Showing the most recent 100 of 276 refreshes on record for this CVE.
A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 176 oldest rows on record are not shown and were not checked, so the counts can still include repeats.
- 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-25 14:22 UTCEG score recompute
- 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-22 22:57 UTCEG score recompute
- 2026-10-22 22:57 UTCVendor advisory
- 2026-10-22 22:57 UTCGHSA enrichmentGHSA-v3cw-2f3g-f38x · GitHub CVSS 4.9
- 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-18 03:33 UTCEG score recompute
- 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-12 15:59 UTCEG score recompute
- 2026-10-11 19:42 UTCEG score recompute
- 2026-10-11 16:57 UTCEG score recompute
- 2026-10-11 14:21 UTCEG score recompute
Show 75 moreShow fewer
- 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.2% · 6th percentile
- 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.2% · 6th percentile
- 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.2% · 6th percentile
- 2026-10-03 12:09 UTCOSV refresh
- 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.2% · 6th percentile
- 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.2% · 6th percentile
- 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.2% · 6th percentile
- 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.2% · 6th percentile
- 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.2% · 6th percentile
- 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.1% · 2nd percentile
- 2026-09-26 00:27 UTCEPSS rescoreEPSS 0.1% · 2nd percentile
- 2026-09-23 17:53 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-09-14 05:28 UTCEG score recompute
- 2026-09-14 05:28 UTCVendor advisory
- 2026-09-14 05:28 UTCGHSA enrichmentGHSA-v3cw-2f3g-f38x · GitHub CVSS 4.9
- 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-09-12 23:36 UTCOSV refresh
- 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-09-10 09:35 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-09-01 04:40 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-08-28 21:41 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-08-26 14:46 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-08-25 13:49 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-08-25 03:35 UTCEG score recompute
- 2026-08-25 03:35 UTCVendor advisory
- 2026-08-25 03:35 UTCGHSA enrichmentGHSA-v3cw-2f3g-f38x · GitHub CVSS 4.9
- 2026-08-23 12:44 UTCEG score recompute
- 2026-08-23 12:44 UTCVendor advisory
- 2026-08-23 12:44 UTCGHSA enrichmentGHSA-v3cw-2f3g-f38x · GitHub CVSS 4.9
- 2026-08-23 00:19 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-08-21 23:49 UTCEPSS rescoreEPSS 0.2% · 7th percentile
- 2026-08-21 07:42 UTCEG score recompute
- 2026-08-21 07:42 UTCVendor advisory
- 2026-08-21 07:42 UTCGHSA enrichmentGHSA-v3cw-2f3g-f38x · GitHub CVSS 4.9
- 2026-08-20 22:55 UTCEPSS rescoreEPSS 0.3% · 21st percentile
- 2026-08-20 09:59 UTCEG score recompute
- 2026-08-20 09:59 UTCVendor advisory
- 2026-08-20 09:59 UTCGHSA enrichmentGHSA-v3cw-2f3g-f38x · GitHub CVSS 4.9
- 2026-08-19 17:04 UTCEPSS rescoreEPSS 0.3% · 21st percentile
- 2026-08-18 13:48 UTCEPSS rescoreEPSS 0.3% · 21st percentile
- 2026-08-17 13:47 UTCEPSS rescoreEPSS 0.3% · 21st percentile
- 2026-08-17 03:34 UTCEG score recompute
- 2026-08-17 03:34 UTCVendor advisory
- 2026-08-17 03:34 UTCGHSA enrichmentGHSA-v3cw-2f3g-f38x · GitHub CVSS 4.9
- 2026-08-16 14:56 UTCEPSS rescoreEPSS 0.3% · 21st percentile
- 2026-08-16 02:16 UTCEG score recompute
- 2026-08-16 02:16 UTCVendor advisory
- 2026-08-16 02:16 UTCGHSA enrichmentGHSA-v3cw-2f3g-f38x · GitHub CVSS 4.9
- 2026-08-16 02:14 UTCEPSS rescoreEPSS 0.3% · 21st percentile
- 2026-08-15 01:41 UTCEG score recompute
- 2026-08-15 01:41 UTCVendor advisory
- 2026-08-15 01:41 UTCGHSA enrichmentGHSA-v3cw-2f3g-f38x · GitHub CVSS 4.9
- 2026-08-15 01:30 UTCEPSS rescoreEPSS 0.3% · 21st percentile
- 2026-08-14 03:59 UTCEG score recompute
- 2026-08-14 03:59 UTCVendor advisory
- 2026-08-14 03:59 UTCGHSA enrichmentGHSA-v3cw-2f3g-f38x · GitHub CVSS 4.9
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Frequently asked(5)
What is CVE-2026-50219?
When was the CVE record for CVE-2026-50219 published?
Is CVE-2026-50219 actively exploited?
What is the CVSS score of CVE-2026-50219?
How do I remediate CVE-2026-50219?
Dependency Blast Radius
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