CVE-2026-45186

HIGHNVD 7.57.5
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to NVD's CVSS score.

This high-severity CVE scores 7.5 under NVD CVSS v3. EPSS exploit probability: 0.5% (41st percentile of EPSS-scored CVEs). GitHub Security Advisory CVSS 2.9 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 2026-05-10) is not newer than that change (2026-10-15), so it does not.

Triggered by: Headline CVSS from NVD CVSS v3
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 4 sources updated this week

Also known asEUVD-2026-28985 (ENISA EUVD) · GHSA-r396-2q2c-pjhr (GitHub Security Advisories)Source: ENISA EUVD

7.5EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.5%CVSS: 7.5Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderately sized crafted XML input.

CVSS v3
7.5
EG Score
7.5HIGHmedium confidence
EG Risk
34
EG Risk 34/100

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)
Severity75% × 45%
Impact severity (EG Severity): CVSS 7.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.5% × 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
0.5%
EPSS %ILE
41st
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 (7.5): severity, escalated by confirmed exploitation. This CVE's 7.5 is its impact severity (EG Severity), not escalated.

EG Severity
7.5 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.NVD CVSS v3 · CVSS v3.0 or v3.1
EG Likelihood
0.5% 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

May 10, 2026

Last Modified

October 15, 2026

Advisory Details (10)

Auto-updated Jul 1, 2026
Patch available. Sources: github_pr, redhat.
Red HatMentions a patch (unverified)

2468575 – (CVE-2026-45186) CVE-2026-45186 libexpat: denial of service via crafted XML input

Affected: Red Hat Enterprise Linux 10

https://bugzilla.redhat.com/show_bug.cgi?id=2468575
Red HatMentions a patch (unverified)

cve-details

https://access.redhat.com/security/cve/CVE-2026-45186
Red HatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:29197
Red HatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:27201
Red HatMentions a patch (unverified)
https://access.redhat.com/errata/RHSA-2026:26319
Red HatMentions a patch (unverified)

Affected: Red Hat Enterprise Linux 9.

https://access.redhat.com/errata/RHSA-2026:23230
Red HatMentions a patch (unverified)

Affected: Red Hat Enterprise Linux 8.

https://access.redhat.com/errata/RHSA-2026:22721
Red HatMentions a patch (unverified)

Affected: Red Hat Enterprise Linux 10.

https://access.redhat.com/errata/RHSA-2026:22715
Web page

oss-security - libexpat 2.8.1 fixes CVE-2026-45186 (denial of service)

http://www.openwall.com/lists/oss-security/2026/05/11/16
GitHub pull request

[CVE-2026-45186] Prevent attribute collision check DoS

Fix merged in libexpat/libexpat PR #1216 on 2026-05-10 — awaiting tagged release

https://github.com/libexpat/libexpat/pull/1216

Patch Availability(9)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntulibexpat1-dev (2.7.4-1ubuntu0.1) @ resolute2026-10-22ubuntu
redhatexpat-main-2.8.5-1.1.hum12026-10-07redhat
redhatrhui5/rhua-tp-rhel9:17872412602026-08-24redhat
redhatdiscovery/discovery-ui-rhel9:17821669522026-06-24redhat
redhatlibexpat-2.dll2026-06-22redhat
redhatrhui5/rhua-rhel9:17815257392026-06-16redhat
redhatexpat-0:2.5.0-6.el9_8.12026-06-04redhat
redhatexpat-0:2.7.3-1.el10_2.12026-06-03redhat
redhatexpat-0:2.5.0-2.el8_102026-06-03redhat

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

(9 across 9 ecosystems)
Alpine:v3.20(1)
PackageVulnerable rangeFix by version rangeDependents
expat—
  • every version up to 2.8.1-r0: fixed in 2.8.1-r0
—
Alpine:v3.21(1)
PackageVulnerable rangeFix by version rangeDependents
expat—
  • every version up to 2.8.1-r0: fixed in 2.8.1-r0
—
Alpine:v3.22(1)
PackageVulnerable rangeFix by version rangeDependents
expat—
  • every version up to 2.8.1-r0: fixed in 2.8.1-r0
—
Alpine:v3.23(1)
PackageVulnerable rangeFix by version rangeDependents
expat—
  • every version up to 2.8.1-r0: fixed in 2.8.1-r0
—
Alpine:v3.24(1)
PackageVulnerable rangeFix by version rangeDependents
expat—
  • every version up to 2.8.1-r0: fixed in 2.8.1-r0
—
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
expat2.2.10-2 ... 2.8.2-1~deb13u1 (47 versions)
  • every version on: no fix on record
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
expat2.5.0-1, 2.5.0-1+deb12u1, 2.5.0-1+deb12u2, 2.5.0-1+deb12u3
  • every version up to 2.5.0-1+deb12u4: fixed in 2.5.0-1+deb12u4
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
expat2.7.1-2 ... 2.8.1-1 (9 versions)
  • every version up to 2.8.2-1~deb13u1: fixed in 2.8.2-1~deb13u1
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
expat2.7.1-2 ... 2.8.0-1 (7 versions)
  • every version up to 2.8.0-2: fixed in 2.8.0-2
—

Weakness Classification(1)

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

Additional Vendor Advisories

(2)

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 / 40× 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 269 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 169 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  2. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  3. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  4. 2026-10-25 14:27 UTCEG score recompute
  5. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  6. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  7. 2026-10-22 18:08 UTCEG score recompute
  8. 2026-10-22 18:08 UTCVendor advisory
  9. 2026-10-22 18:08 UTCGHSA enrichmentGHSA-r396-2q2c-pjhr · GitHub severity LOW · GitHub CVSS 2.9
  10. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  11. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  12. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  13. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.5% · 40th percentile
  14. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  15. 2026-10-18 03:38 UTCEG score recompute
  16. 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  17. 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  18. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  19. 2026-10-15 01:36 UTCEG score recompute
  20. 2026-10-15 01:36 UTCVendor advisory
  21. 2026-10-15 01:36 UTCGHSA enrichmentGHSA-r396-2q2c-pjhr · GitHub severity LOW · GitHub CVSS 2.9
  22. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  23. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  24. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  25. 2026-10-12 16:04 UTCEG score recompute
Show 75 more
  1. 2026-10-11 19:46 UTCEG score recompute
  2. 2026-10-11 17:01 UTCEG score recompute
  3. 2026-10-11 14:26 UTCEG score recompute
  4. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  5. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  6. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  7. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  8. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  9. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  10. 2026-10-06 05:45 UTCOSV refresh
  11. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  12. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  13. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  14. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  15. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  16. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  17. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.6% · 44th percentile
  18. 2026-09-23 17:53 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  19. 2026-09-20 20:15 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  20. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.5% · 39th percentile
  21. 2026-09-17 19:31 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  22. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  23. 2026-09-16 13:43 UTCVendor advisory
  24. 2026-09-16 13:43 UTCGHSA enrichmentGHSA-r396-2q2c-pjhr · GitHub severity LOW · GitHub CVSS 2.9
  25. 2026-09-16 12:21 UTCEG score recompute
  26. 2026-09-16 12:21 UTCVendor advisory
  27. 2026-09-16 12:21 UTCGHSA enrichmentGHSA-r396-2q2c-pjhr · GitHub severity LOW · GitHub CVSS 2.9
  28. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  29. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  30. 2026-09-13 11:54 UTCOSV refresh
  31. 2026-09-12 15:01 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  32. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  33. 2026-09-11 09:37 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  34. 2026-09-10 09:34 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  35. 2026-09-08 22:00 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  36. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  37. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  38. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  39. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  40. 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  41. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  42. 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  43. 2026-08-28 21:41 UTCEPSS rescoreEPSS 0.5% · 37th percentile
  44. 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  45. 2026-08-26 14:46 UTCEPSS rescoreEPSS 0.5% · 38th percentile
  46. 2026-08-25 13:49 UTCEPSS rescoreEPSS 0.4% · 36th percentile
  47. 2026-08-25 13:24 UTCVendor advisory
  48. 2026-08-25 13:24 UTCGHSA enrichmentGHSA-r396-2q2c-pjhr · GitHub severity LOW · GitHub CVSS 2.9
  49. 2026-08-25 12:21 UTCEG score recompute
  50. 2026-08-25 12:21 UTCVendor advisory
  51. 2026-08-25 12:21 UTCGHSA enrichmentGHSA-r396-2q2c-pjhr · GitHub severity LOW · GitHub CVSS 2.9
  52. 2026-08-23 18:47 UTCEG score recompute
  53. 2026-08-23 18:47 UTCVendor advisory
  54. 2026-08-23 18:47 UTCGHSA enrichmentGHSA-r396-2q2c-pjhr · GitHub severity LOW · GitHub CVSS 2.9
  55. 2026-08-23 00:19 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  56. 2026-08-21 23:49 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  57. 2026-08-20 22:55 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  58. 2026-08-19 17:04 UTCEPSS rescoreEPSS 0.4% · 37th percentile
  59. 2026-08-18 13:48 UTCEPSS rescoreEPSS 0.4% · 36th percentile
  60. 2026-08-17 13:47 UTCEPSS rescoreEPSS 0.4% · 36th percentile
  61. 2026-08-17 11:21 UTCEG score recompute
  62. 2026-08-17 11:21 UTCVendor advisory
  63. 2026-08-17 11:21 UTCGHSA enrichmentGHSA-r396-2q2c-pjhr · GitHub severity LOW · GitHub CVSS 2.9
  64. 2026-08-16 14:56 UTCEPSS rescoreEPSS 0.4% · 36th percentile
  65. 2026-08-16 04:29 UTCEG score recompute
  66. 2026-08-16 04:29 UTCVendor advisory
  67. 2026-08-16 04:29 UTCGHSA enrichmentGHSA-r396-2q2c-pjhr · GitHub severity LOW · GitHub CVSS 2.9
  68. 2026-08-16 02:14 UTCEPSS rescoreEPSS 0.4% · 36th percentile
  69. 2026-08-15 01:44 UTCEG score recompute
  70. 2026-08-15 01:44 UTCVendor advisory
  71. 2026-08-15 01:44 UTCGHSA enrichmentGHSA-r396-2q2c-pjhr · GitHub severity LOW · GitHub CVSS 2.9
  72. 2026-08-15 01:30 UTCEPSS rescoreEPSS 0.4% · 36th percentile
  73. 2026-08-14 14:24 UTCVendor advisory
  74. 2026-08-14 14:24 UTCGHSA enrichmentGHSA-r396-2q2c-pjhr · GitHub severity LOW · GitHub CVSS 2.9
  75. 2026-08-14 03:04 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-45186?
CVE-2026-45186 is a high-severity vulnerability; its CVE record was published on May 10, 2026. In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderately sized crafted XML input.
When was the CVE record for CVE-2026-45186 published?
The CVE record for CVE-2026-45186 was published on May 10, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of October 15, 2026; the record at its source may have been updated since.
Is CVE-2026-45186 actively exploited?
CVE-2026-45186 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.5% probability of exploitation in the next 30 days (41st percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-45186?
CVE-2026-45186 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-45186?
A fix for CVE-2026-45186 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-45186 are linked in the Vendor Advisories panel on this page.

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