CVE-2026-25896

CRITICALPre-NVD 9.39.3—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.5%, top 61% 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
9.3EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.5%CVSS: 9.3Exploit: Elevated riskExposed services: Not assessed

A fix is available — apply it.

fast-xml-parser allows users to validate XML, parse XML to JS object, or build XML from JS object without C/C++ based libraries and no callback. From 4.1.3to before 5.3.5, a dot (.) in a DOCTYPE entity name is treated as a regex wildcard during entity replacement, allowing an attacker to shadow built-in XML entities (<, >, &, ", ') with arbitrary values. This bypasses entity encoding and leads to XSS when parsed output is rendered. This vulnerability is fixed in 5.3.5.

CVSS v3
9.3
EG Score
9.3CRITICALmedium confidence
EG Risk
73
EG Risk 73/100

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
Severity93% × 45%
Exploitation40% × 40%
Automatability100% × 15%
EPSS PROB
0.5%
EPSS %ILE
40th
KEV
Not listed

Published

February 20, 2026

Last Modified

September 10, 2026

Advisory Details (14)

Auto-updated Oct 3, 2026
🔬 Proof of concept available. Patch available. Sources: github_release, github, redhat, github_commit.
redhat Patch Available
https://access.redhat.com/errata/RHSA-2026:6802
redhat Patch Available
https://access.redhat.com/errata/RHSA-2026:6174
redhat Patch Available
https://access.redhat.com/errata/RHSA-2026:51349
redhat Patch Available
https://access.redhat.com/errata/RHSA-2026:41944
redhat Patch Available
https://access.redhat.com/errata/RHSA-2026:41941
redhat Patch Available
https://access.redhat.com/errata/RHSA-2026:40984
github Patch Available🟡 PoC Available

Entity encoding bypass via regex injection in DOCTYPE entity names · Advisory · NaturalIntelligence/fast-xml-parser · GitHub

https://github.com/NaturalIntelligence/fast-xml-parser/security/advisories/GHSA-m7jm-9gc2-mpf2
github_release Patch Available

v5.3.5

Patch available: NaturalIntelligence/fast-xml-parser v5.3.5

https://github.com/NaturalIntelligence/fast-xml-parser/releases/tag/v5.3.5
github_commit Patch Available

commit ddcd0acf26dd (NaturalIntelligence/fast-xml-parser)

Patch available: NaturalIntelligence/fast-xml-parser v5.3.5 (contains commit ddcd0acf26dd)

https://github.com/NaturalIntelligence/fast-xml-parser/commit/ddcd0acf26ddd682cb0dc15a2bd6aa3b96bb1e69
github_commit Patch Available

commit 943ef0eb1b2d (NaturalIntelligence/fast-xml-parser)

Patch available: NaturalIntelligence/fast-xml-parser v5.3.5 (contains commit 943ef0eb1b2d)

https://github.com/NaturalIntelligence/fast-xml-parser/commit/943ef0eb1b2d3284e72dd74f44a042ee9f07026e
redhat

2441501 – (CVE-2026-25896) CVE-2026-25896 fast-xml-parser: fast-xml-parser: Cross-Site Scripting (XSS) due to improper DOCTYPE entity handling

https://bugzilla.redhat.com/show_bug.cgi?id=2441501
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2026-25896
redhat Patch Available
https://access.redhat.com/errata/RHSA-2026:7128
redhat Patch Available
https://access.redhat.com/errata/RHSA-2026:7110

Vendor Advisories for CVE-2026-25896(8)

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

Patch Availability(8)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatsatellite/iop-host-inventory-frontend-rhel9:17859227642026-08-06redhat
redhatodf4/rook-ceph-rhel9-operator:17836775332026-07-20redhat
redhatodf4/rook-ceph-rhel9-operator:17836853752026-07-20redhat
redhatodf4/rook-ceph-rhel9-operator:17836692192026-07-16redhat
redhatadvanced-cluster-security/rhacs-main-rhel8:17755942842026-04-08redhat
redhatadvanced-cluster-security/rhacs-main-rhel8:17755941192026-04-08redhat
redhatrhdh/rhdh-hub-rhel9:17751406472026-04-07redhat
redhatrhdh/rhdh-hub-rhel9:17745456052026-03-30redhat

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

(4 across 4 ecosystems)
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
node-webfont11.4.0+dfsg2+~cs35.7.26-10 ... 11.4.0+dfsg2+~cs35.7.26-9 (14 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
node-webfont11.4.0+dfsg2+~cs35.7.26-13 ... 11.4.0+dfsg2+~cs35.7.26-21 (8 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
node-webfont11.4.0+dfsg2+~cs35.7.26-13 ... 11.4.0+dfsg2+~cs35.7.26-21 (8 versions)
  • every version on: no fix on record
—
npm(1)
PackageVulnerable rangeFix by version rangeDependents
fast-xml-parser—
  • 5.0.0 up to 5.3.5: fixed in 5.3.5
  • 4.1.3 up to 4.5.4: fixed in 4.5.4
—

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 6× in last 7d / 29× 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.

Showing the most recent 100 of 182 total refreshes for this CVE.

  1. 2026-10-05 17:42 UTCEPSS rescore
  2. 2026-10-04 23:21 UTCEPSS rescore
  3. 2026-10-03 14:25 UTCEPSS rescore
  4. 2026-10-01 19:49 UTCEPSS rescore
  5. 2026-09-30 15:03 UTCEPSS rescore
  6. 2026-09-29 19:32 UTCOSV refresh
  7. 2026-09-28 13:51 UTCEPSS rescore
  8. 2026-09-26 15:58 UTCEPSS rescore
  9. 2026-09-26 00:26 UTCEPSS rescore
  10. 2026-09-20 20:15 UTCEPSS rescore
  11. 2026-09-18 19:27 UTCEPSS rescore
  12. 2026-09-16 14:07 UTCEPSS rescore
  13. 2026-09-16 05:15 UTCEPSS rescore
  14. 2026-09-13 16:47 UTCEPSS rescore
  15. 2026-09-12 15:01 UTCEPSS rescore
  16. 2026-09-11 14:52 UTCEPSS rescore
  17. 2026-09-10 13:23 UTCEG score recompute
  18. 2026-09-10 13:23 UTCVendor advisory
  19. 2026-09-10 12:28 UTCEG score recompute
  20. 2026-09-10 12:28 UTCVendor advisory
  21. 2026-09-10 09:34 UTCEPSS rescore
  22. 2026-09-09 12:41 UTCEG score recompute
  23. 2026-09-09 12:41 UTCVendor advisory
  24. 2026-09-08 22:00 UTCEPSS rescore
  25. 2026-09-07 16:01 UTCEPSS rescore
Show 75 more
  1. 2026-09-07 14:04 UTCEG score recompute
  2. 2026-09-07 14:04 UTCVendor advisory
  3. 2026-09-06 13:47 UTCEPSS rescore
  4. 2026-09-06 13:47 UTCEPSS rescore
  5. 2026-09-04 05:06 UTCEPSS rescore
  6. 2026-09-02 14:11 UTCEPSS rescore
  7. 2026-09-02 13:43 UTCEG score recompute
  8. 2026-09-02 13:43 UTCVendor advisory
  9. 2026-09-02 12:39 UTCEG score recompute
  10. 2026-09-02 12:39 UTCVendor advisory
  11. 2026-09-01 13:53 UTCEPSS rescore
  12. 2026-09-01 04:39 UTCEPSS rescore
  13. 2026-08-30 19:17 UTCEPSS rescore
  14. 2026-08-30 01:22 UTCEPSS rescore
  15. 2026-08-28 21:41 UTCEPSS rescore
  16. 2026-08-27 14:25 UTCEPSS rescore
  17. 2026-08-26 14:46 UTCEPSS rescore
  18. 2026-08-25 13:48 UTCEPSS rescore
  19. 2026-08-24 13:32 UTCEG score recompute
  20. 2026-08-24 13:32 UTCVendor advisory
  21. 2026-08-24 12:28 UTCEG score recompute
  22. 2026-08-24 12:28 UTCVendor advisory
  23. 2026-08-23 00:19 UTCEPSS rescore
  24. 2026-08-21 23:49 UTCEPSS rescore
  25. 2026-08-20 22:55 UTCEPSS rescore
  26. 2026-08-20 13:59 UTCEG score recompute
  27. 2026-08-20 13:59 UTCVendor advisory
  28. 2026-08-20 12:46 UTCEG score recompute
  29. 2026-08-20 12:46 UTCVendor advisory
  30. 2026-08-19 17:03 UTCEPSS rescore
  31. 2026-08-19 12:12 UTCEG score recompute
  32. 2026-08-19 12:12 UTCVendor advisory
  33. 2026-08-18 13:48 UTCEPSS rescore
  34. 2026-08-18 12:23 UTCEG score recompute
  35. 2026-08-18 12:23 UTCVendor advisory
  36. 2026-08-17 13:47 UTCEPSS rescore
  37. 2026-08-17 12:22 UTCEG score recompute
  38. 2026-08-17 12:22 UTCVendor advisory
  39. 2026-08-17 12:14 UTCEG score recompute
  40. 2026-08-17 12:14 UTCVendor advisory
  41. 2026-08-16 14:56 UTCEPSS rescore
  42. 2026-08-16 02:14 UTCEPSS rescore
  43. 2026-08-15 01:30 UTCEPSS rescore
  44. 2026-08-15 01:18 UTCVendor advisory
  45. 2026-08-14 21:35 UTCVendor advisory
  46. 2026-08-14 13:28 UTCEG score recompute
  47. 2026-08-14 13:28 UTCVendor advisory
  48. 2026-08-14 12:30 UTCEG score recompute
  49. 2026-08-14 12:30 UTCVendor advisory
  50. 2026-08-14 09:20 UTCEG score recompute
  51. 2026-08-14 09:20 UTCVendor advisory
  52. 2026-08-13 22:00 UTCEPSS rescore
  53. 2026-08-13 01:24 UTCEG score recompute
  54. 2026-08-13 01:24 UTCVendor advisory
  55. 2026-08-12 13:50 UTCEPSS rescore
  56. 2026-08-12 12:39 UTCEG score recompute
  57. 2026-08-12 12:39 UTCVendor advisory
  58. 2026-08-12 12:14 UTCEG score recompute
  59. 2026-08-12 12:14 UTCVendor advisory
  60. 2026-08-12 01:34 UTCEG score recompute
  61. 2026-08-12 01:34 UTCVendor advisory
  62. 2026-08-11 13:42 UTCEPSS rescore
  63. 2026-08-11 06:51 UTCEG score recompute
  64. 2026-08-11 06:51 UTCVendor advisory
  65. 2026-08-11 00:00 UTCEPSS rescore
  66. 2026-08-10 13:22 UTCEG score recompute
  67. 2026-08-10 13:22 UTCVendor advisory
  68. 2026-08-10 12:27 UTCEG score recompute
  69. 2026-08-10 12:27 UTCVendor advisory
  70. 2026-08-10 09:19 UTCVendor advisory
  71. 2026-08-10 01:17 UTCVendor advisory
  72. 2026-08-09 21:35 UTCVendor advisory
  73. 2026-08-09 17:51 UTCVendor advisory
  74. 2026-08-09 13:55 UTCEG score recompute
  75. 2026-08-09 13:55 UTCVendor advisory

Related CVEs(same product + same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-25896?
CVE-2026-25896 is a critical vulnerability published on February 20, 2026. fast-xml-parser allows users to validate XML, parse XML to JS object, or build XML from JS object without C/C++ based libraries and no callback. From 4.1.3to before 5.3.5, a dot (.) in a DOCTYPE entity name is treated as a regex wildcard during entity replacement, allowing an attacker to shadow…
When was CVE-2026-25896 disclosed?
CVE-2026-25896 was first published on February 20, 2026, with the most recent update on September 10, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-25896 actively exploited?
CVE-2026-25896 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.5% probability of exploitation in the next 30 days (40th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-25896?
CVE-2026-25896 has a CVSS base score of 9.3 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-25896?
A fix for CVE-2026-25896 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-25896 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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