CVE-2026-41401

MEDIUMNVD 6.56.5
EchelonGraph scoreMEDIUM confidence

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

Score 6.5 from GitHub Security Advisory (severity: HIGH) published 2026-05-26. NVD baseline CVSS 6.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Elevated

Also known asEUVD-2026-31832 (ENISA EUVD) · GHSA-v7jp-vmx6-5429 (GitHub Security Advisories)Source: ENISA EUVD

6.5EG
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: 0.7%CVSS: 6.5Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

libyang before 5.4.3 contains a heap use-after-free write vulnerability in lyd_parser_set_data_flags that incorrectly updates metadata list pointers when freeing non-head default metadata entries. Attackers can trigger this vulnerability by submitting crafted YANG XML documents with specific metadata attributes to applications parsing untrusted XML data, causing process crashes or potential code execution.

CVSS v3
6.5
EG Score
6.5MEDIUMmedium confidence
EG Risk
45
EG Risk 45/100

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)
Severity65% × 45%
Impact severity (EG Severity): CVSS 6.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.
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
0.7%
EPSS %ILE
52nd
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 (6.5): severity, escalated by confirmed exploitation. This CVE's 6.5 is its impact severity (EG Severity), not escalated.

EG Severity
6.5 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.7% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-07). 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 low or medium mission impact; Track* at high (mission-essential systems).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, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

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.

The score's inputs: 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 26, 2026

Last Modified

November 8, 2026

Advisory Details (4)

Auto-updated Jun 13, 2026
Patch available. Sources: github_commit, github.
GitHub advisoryMentions a patch (unverified)

Heap Use-After-Free write in libyang XML metadata parsing (lyd_parse_data_mem / lyd_parse_mem_xml) · Advisory · CESNET/libyang · GitHub

https://github.com/CESNET/libyang/security/advisories/GHSA-9f49-8x56-jmjc
Web page

libyang - Heap Use-After-Free Write in XML Metadata Parsing | Advisories | VulnCheck

https://www.vulncheck.com/advisories/libyang-heap-use-after-free-write-in-xml-metadata-parsing
GitHub commit Patch Available

commit 6b5ed47ee674 (CESNET/libyang)

Patch available: CESNET/libyang v5.4.9 (contains commit 6b5ed47ee674)

https://github.com/CESNET/libyang/commit/6b5ed47ee674fbe86b31bbebc4ff26889aeff38c

Vendor Advisories for CVE-2026-41401(2)

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

Patch Availability(1)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntulibyang3-tools (3.13.6-1ubuntu0.1) @ resolute2026-10-29ubuntu

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:11(1)
PackageVulnerable rangeFix by version rangeDependents
libyang1.0.225-1.1 ... 6.1.4-1 (29 versions)
  • every version on: no fix on record
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
libyang22.1.148-0.1, 2.1.148-0.2, 2.1.30-2, 2.1.30-2.1, 2.1.30-2.1~exp1
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
libyang3.12.2-1 ... 6.4.6-1 (25 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
libyang3.12.2-1 ... 6.4.6-1 (24 versions)
  • every version up to 6.4.13-1: fixed in 6.4.13-1
—

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 9× in last 7d / 41× 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 its CVE.org record (CNA or CISA ADP). 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). "EchelonGraph re-scored" is our own recompute of this CVE's score, not an update from a source, and is not counted in the refreshes above. Most recent first.

Showing the most recent 100 of 314 rows 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 214 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-12 16:33 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  2. 2026-11-11 16:39 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  3. 2026-11-10 16:44 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  4. 2026-11-09 16:35 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  5. 2026-11-08 16:39 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  6. 2026-11-08 14:21 UTCEchelonGraph re-scored
  7. 2026-11-08 14:21 UTCVendor advisory
  8. 2026-11-08 14:21 UTCGHSA enrichmentGHSA-v7jp-vmx6-5429 · GitHub severity HIGH · GitHub CVSS 6.5
  9. 2026-11-07 16:39 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  10. 2026-11-06 16:37 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  11. 2026-11-05 16:37 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  12. 2026-11-04 16:35 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  13. 2026-11-04 01:55 UTCEchelonGraph re-scored
  14. 2026-11-04 01:55 UTCVendor advisory
  15. 2026-11-04 01:55 UTCGHSA enrichmentGHSA-v7jp-vmx6-5429 · GitHub severity HIGH · GitHub CVSS 6.5
  16. 2026-11-03 16:48 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  17. 2026-11-02 16:44 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  18. 2026-11-01 16:34 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  19. 2026-10-31 16:32 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  20. 2026-10-30 16:34 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  21. 2026-10-29 21:28 UTCVendor advisory
  22. 2026-10-29 21:28 UTCGHSA enrichmentGHSA-v7jp-vmx6-5429 · GitHub severity HIGH · GitHub CVSS 6.5
  23. 2026-10-29 21:26 UTCNVD updateCVSS v4 → 7.1
  24. 2026-10-29 20:28 UTCEchelonGraph re-scored
  25. 2026-10-29 20:28 UTCVendor advisory
Show 75 more
  1. 2026-10-29 20:28 UTCGHSA enrichmentGHSA-v7jp-vmx6-5429 · GitHub severity HIGH · GitHub CVSS 6.5
  2. 2026-10-29 16:33 UTCEPSS rescoreEPSS 0.7% · 52nd percentile
  3. 2026-10-28 16:32 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  4. 2026-10-27 16:32 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  5. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  6. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.7% · 51st percentile
  7. 2026-10-25 14:30 UTCEchelonGraph re-scored
  8. 2026-10-24 16:32 UTCEPSS rescoreEPSS 0.6% · 50th percentile
  9. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.6% · 50th percentile
  10. 2026-10-23 02:21 UTCEchelonGraph re-scored
  11. 2026-10-23 02:21 UTCVendor advisory
  12. 2026-10-23 02:21 UTCGHSA enrichmentGHSA-v7jp-vmx6-5429 · GitHub severity HIGH · GitHub CVSS 6.5
  13. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.6% · 50th percentile
  14. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.6% · 50th percentile
  15. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  16. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  17. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  18. 2026-10-18 03:41 UTCEchelonGraph re-scored
  19. 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  20. 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  21. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  22. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  23. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  24. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  25. 2026-10-12 16:08 UTCEchelonGraph re-scored
  26. 2026-10-11 19:50 UTCEchelonGraph re-scored
  27. 2026-10-11 17:04 UTCEchelonGraph re-scored
  28. 2026-10-11 14:30 UTCEchelonGraph re-scored
  29. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  30. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  31. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  32. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  33. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.6% · 49th percentile
  34. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  35. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  36. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  37. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  38. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  39. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  40. 2026-09-30 01:39 UTCOSV refresh
  41. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  42. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.6% · 48th percentile
  43. 2026-09-23 17:53 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  44. 2026-09-20 20:15 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  45. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.5% · 43rd percentile
  46. 2026-09-17 19:31 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  47. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  48. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  49. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  50. 2026-09-12 15:01 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  51. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  52. 2026-09-11 09:37 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  53. 2026-09-11 01:53 UTCOSV refresh
  54. 2026-09-10 09:34 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  55. 2026-09-08 22:00 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  56. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  57. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  58. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  59. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  60. 2026-09-01 13:53 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  61. 2026-09-01 04:39 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  62. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  63. 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  64. 2026-08-28 21:41 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  65. 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  66. 2026-08-26 14:46 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  67. 2026-08-25 13:49 UTCEPSS rescoreEPSS 0.5% · 41st percentile
  68. 2026-08-23 16:21 UTCEchelonGraph re-scored
  69. 2026-08-23 16:21 UTCVendor advisory
  70. 2026-08-23 16:21 UTCGHSA enrichmentGHSA-v7jp-vmx6-5429 · GitHub severity HIGH · GitHub CVSS 6.5
  71. 2026-08-23 00:19 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  72. 2026-08-21 23:49 UTCEPSS rescoreEPSS 0.5% · 42nd percentile
  73. 2026-08-21 21:28 UTCEchelonGraph re-scored
  74. 2026-08-21 21:28 UTCVendor advisory
  75. 2026-08-21 21:28 UTCGHSA enrichmentGHSA-v7jp-vmx6-5429 · GitHub severity HIGH · GitHub CVSS 6.5

Frequently asked(5)

What is CVE-2026-41401?
CVE-2026-41401 is a medium-severity vulnerability; its CVE record was published on May 26, 2026. libyang before 5.4.3 contains a heap use-after-free write vulnerability in lyd_parser_set_data_flags that incorrectly updates metadata list pointers when freeing non-head default metadata entries. Attackers can trigger this vulnerability by submitting crafted YANG XML documents with specific…
When was CVE-2026-41401 made public?
CVE-2026-41401 was made public on March 26, 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 May 26, 2026. EchelonGraph's copy of the record carries a last-modified date of November 8, 2026; the record at its source may have been updated since.
Is CVE-2026-41401 actively exploited?
CVE-2026-41401 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.7% probability of exploitation in the next 30 days (52nd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-41401?
CVE-2026-41401 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2026-41401?
A fix for CVE-2026-41401 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-41401 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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