CVE-2026-64323

HIGHPre-NVD 7.17.1
EchelonGraph scoreMEDIUM confidence

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

Score 7.1 from GitHub Security Advisory (severity: HIGH) published 2026-07-25. A secondary CVSS source baseline 7.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, a secondary CVSS source
Trending — 4 sources updated this week
7.1EG
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: 0.2%CVSS: 7.1Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

In the Linux kernel, the following vulnerability has been resolved:

udf: validate VAT header length against the VAT inode size

udf_load_vat() takes the virtual partition's start offset straight from the on-disk VAT 2.0 header without checking it against the VAT inode size:

map->s_type_specific.s_virtual.s_start_offset = le16_to_cpu(vat20->lengthHeader); map->s_type_specific.s_virtual.s_num_entries = (sbi->s_vat_inode->i_size - map->s_type_specific.s_virtual.s_start_offset) >> 2;

lengthHeader is a fully attacker-controlled 16-bit value. If it exceeds the VAT inode size, the s_num_entries subtraction underflows to a huge count, which defeats the "block > s_num_entries" bound in udf_get_pblock_virt15(); and on the ICB-inline path that function reads

((__le32 *)(iinfo->i_data + s_start_offset))[block]

so a large s_start_offset indexes past the inode's in-ICB data. Mounting a crafted UDF image with a virtual (VAT) partition then triggers an out-of-bounds read.

Reject a VAT whose header length does not leave room for at least one entry within the VAT inode.

CVSS v3
7.1
EG Score
7.1HIGHmedium confidence
EG Risk
32
EG Risk 32/100

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)
Severity71% × 45%
The EG Score, 7.1 of 10.
Exploitation0.2% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's BOD 26-04 default: no one has published Automatable for this CVE, and CISA treats it as “no” for a CVE not in KEV.
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).
Exploitation none (no CISA value, KEV listing or exploit code on record) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from 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
5th
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 none (no CISA value, KEV listing or exploit code on record) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from 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)14 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's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). Where an input reads “CISA's BOD 26-04 default”, no one has published it for this CVE, and CISA's implementation guidance says: “If “Automatable” and “Technical Impact” information items about a CVE ID are not available and the CVE ID is not in the KEV Catalog, CISA will treat its values as “no” and “total,” respectively, until CISA or a third party provides metadata about the CVE ID. CISA will always provide the Vulnrichment data for a CVE ID listed in the KEV Catalog.” 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

July 25, 2026

Last Modified

September 4, 2026

Advisory Details (8)

Auto-updated Jul 27, 2026
Patch available.
Web page

udf: validate VAT header length against the VAT inode size - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/e610fb113cdfa8bf4247c9bf4f2337b81ad4ddad
Web page

udf: validate VAT header length against the VAT inode size - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d8202786b3d75125c84ebc4de6d946f92fde0ee8
Web page

udf: validate VAT header length against the VAT inode size - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/bb0d384c1f42a5b7ace0bd88fee80b9bb1d49acb
Web page

udf: validate VAT header length against the VAT inode size - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/883962731420ec271ed8c1cd76524f4b17faa982
Web page

udf: validate VAT header length against the VAT inode size - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/74580fdf022909e184223cacc364feb826982d96
Web page

udf: validate VAT header length against the VAT inode size - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/55287a3555ff0515b3aff181d2c08c0462a41709
Web page

udf: validate VAT header length against the VAT inode size - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/2900e02a0dd4fc30ac9840e7ce4ca0b041ab0d63
Web page

udf: validate VAT header length against the VAT inode size - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/0ad2d09a8d66fa8dc6f9b70d660b5fb4478ea934

Vendor Advisories for CVE-2026-64323(2)

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

Patch Availability(17)

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

(6 across 4 ecosystems)
Debian:11(2)
PackageVulnerable rangeFix by version rangeDependents
linux5.10.103-1 ... 5.10.92-2 (55 versions)
  • every version up to 5.10.262-1: fixed in 5.10.262-1
—
linux-6.16.1.106-3~deb11u1 ... 6.1.177-1~deb11u1 (22 versions)
  • every version up to 6.1.180-1~deb11u1: fixed in 6.1.180-1~deb11u1
—
Debian:12(2)
PackageVulnerable rangeFix by version rangeDependents
linux6.1.106-1 ... 6.1.99-1 (55 versions)
  • every version up to 6.1.180-1: fixed in 6.1.180-1
—
linux-6.12—
  • every version up to 6.12.100-1~deb12u1: fixed in 6.12.100-1~deb12u1
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
linux6.12.38-1 ... 6.12.95-1~bpo12+1 (30 versions)
  • every version up to 6.12.96-1: fixed in 6.12.96-1
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
linux6.12.100-1 ... 7.1~rc7-1~exp1 (159 versions)
  • every version up to 7.1.4-1: fixed in 7.1.4-1
—

Weakness Classification(1)

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

Additional Vendor Advisories

(17)

Data Freshness Timeline

(refreshed 14× in last 7d / 74× 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 305 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 205 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  2. 2026-10-13 11:43 UTCEG score recompute
  3. 2026-10-13 11:43 UTCVendor advisory
  4. 2026-10-13 11:43 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  5. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  6. 2026-10-12 15:48 UTCEG score recompute
  7. 2026-10-11 19:32 UTCEG score recompute
  8. 2026-10-11 16:47 UTCEG score recompute
  9. 2026-10-11 14:09 UTCEG score recompute
  10. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  11. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  12. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  13. 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  14. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  15. 2026-10-07 06:17 UTCEG score recompute
  16. 2026-10-07 06:17 UTCVendor advisory
  17. 2026-10-07 06:17 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  18. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  19. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  20. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  21. 2026-10-04 07:37 UTCEG score recompute
  22. 2026-10-04 07:37 UTCVendor advisory
  23. 2026-10-04 07:37 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  24. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  25. 2026-10-02 19:34 UTCEG score recompute
Show 75 more
  1. 2026-10-02 19:34 UTCVendor advisory
  2. 2026-10-02 19:34 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  3. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  4. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  5. 2026-10-01 04:19 UTCEG score recompute
  6. 2026-10-01 04:19 UTCVendor advisory
  7. 2026-10-01 04:18 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  8. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  9. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  10. 2026-09-28 04:19 UTCEG score recompute
  11. 2026-09-28 04:19 UTCVendor advisory
  12. 2026-09-28 04:18 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  13. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  14. 2026-09-25 09:52 UTCEG score recompute
  15. 2026-09-25 09:52 UTCVendor advisory
  16. 2026-09-25 09:52 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  17. 2026-09-24 13:08 UTCVendor advisory
  18. 2026-09-24 13:08 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  19. 2026-09-24 00:52 UTCEG score recompute
  20. 2026-09-24 00:52 UTCVendor advisory
  21. 2026-09-24 00:51 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  22. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  23. 2026-09-23 10:24 UTCVendor advisory
  24. 2026-09-23 10:24 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  25. 2026-09-22 22:05 UTCEG score recompute
  26. 2026-09-22 22:05 UTCVendor advisory
  27. 2026-09-22 22:05 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  28. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  29. 2026-09-20 01:31 UTCEG score recompute
  30. 2026-09-20 01:31 UTCVendor advisory
  31. 2026-09-20 01:31 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  32. 2026-09-18 19:52 UTCEG score recompute
  33. 2026-09-18 19:52 UTCVendor advisory
  34. 2026-09-18 19:52 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  35. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  36. 2026-09-18 02:50 UTCEG score recompute
  37. 2026-09-18 02:50 UTCVendor advisory
  38. 2026-09-18 02:49 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  39. 2026-09-17 01:56 UTCEG score recompute
  40. 2026-09-17 01:56 UTCVendor advisory
  41. 2026-09-17 01:56 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  42. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.2% · 6th percentile
  43. 2026-09-16 06:33 UTCEG score recompute
  44. 2026-09-16 06:33 UTCVendor advisory
  45. 2026-09-16 06:33 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  46. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  47. 2026-09-15 09:26 UTCEG score recompute
  48. 2026-09-15 09:26 UTCVendor advisory
  49. 2026-09-15 09:26 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  50. 2026-09-14 06:35 UTCVendor advisory
  51. 2026-09-14 06:35 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  52. 2026-09-13 18:19 UTCEG score recompute
  53. 2026-09-13 18:19 UTCVendor advisory
  54. 2026-09-13 18:19 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  55. 2026-09-13 05:57 UTCVendor advisory
  56. 2026-09-13 05:57 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  57. 2026-09-12 17:40 UTCEG score recompute
  58. 2026-09-12 17:40 UTCVendor advisory
  59. 2026-09-12 17:40 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  60. 2026-09-12 05:00 UTCVendor advisory
  61. 2026-09-12 05:00 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  62. 2026-09-11 16:27 UTCEG score recompute
  63. 2026-09-11 16:27 UTCVendor advisory
  64. 2026-09-11 16:27 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  65. 2026-09-11 09:37 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  66. 2026-09-11 02:19 UTCVendor advisory
  67. 2026-09-11 02:19 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  68. 2026-09-10 13:28 UTCEG score recompute
  69. 2026-09-10 13:28 UTCVendor advisory
  70. 2026-09-10 13:28 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  71. 2026-09-09 08:38 UTCEG score recompute
  72. 2026-09-09 08:38 UTCVendor advisory
  73. 2026-09-09 08:38 UTCGHSA enrichmentGHSA-rjqr-92w7-gfg4 · GitHub severity HIGH · GitHub CVSS 7.1
  74. 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.2% · 5th percentile
  75. 2026-09-07 21:18 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-64323?
CVE-2026-64323 is a high-severity vulnerability; its CVE record was published on July 25, 2026. In the Linux kernel, the following vulnerability has been resolved: udf: validate VAT header length against the VAT inode size udfloadvat() takes the virtual partition's start offset straight from the on-disk VAT 2.0 header without checking it against the VAT inode size:…
When was the CVE record for CVE-2026-64323 published?
The CVE record for CVE-2026-64323 was published on July 25, 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 September 4, 2026; the record at its source may have been updated since.
Is CVE-2026-64323 actively exploited?
CVE-2026-64323 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (5th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-64323?
CVE-2026-64323 has a CVSS base score of 7.1 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-64323?
A fix for CVE-2026-64323 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-64323 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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