CVE-2026-81726

HIGHPre-NVD 7.07.0
EchelonGraph scoreMEDIUM confidence

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

Score 7.0 from GitHub Security Advisory (severity: HIGH) published 2026-09-02. A secondary CVSS source baseline 7.0; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, a secondary CVSS source
Trending — 3 sources updated this weekElevated
7.0EG
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: 0.3%CVSS: 7.0Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

NLTK through 3.10.3 contains a path traversal vulnerability in model-artifact APIs that bypass pathsec enforcement by using raw file operations on caller-controlled paths. Attackers can read or write files outside allowed sandbox roots through TransitionParser, AveragedPerceptron, PerceptronTagger, and maxent parameter APIs when pathsec is enabled.

CVSS v3
7.0
EG Score
7.0HIGHmedium confidence
EG Risk
48
EG Risk 48/100

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)
Severity70% × 45%
The EG Score, 7.0 of 10.
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
0.3%
EPSS %ILE
25th
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 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.

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

August 27, 2026

Last Modified

August 31, 2026

Advisory Details (2)

Auto-updated Aug 27, 2026
Patch available. Sources: github.
Web page

NLTK through 3.10.3 Path Traversal via Model-Artifact APIs | Advisories | VulnCheck

https://www.vulncheck.com/advisories/nltk-through-3.10.3-path-traversal-via-model-artifact-apis
GitHub advisoryMentions a patch (unverified)

Model-artifact APIs bypass pathsec and touch files outside allowed roots · Advisory · nltk/nltk · GitHub

https://github.com/nltk/nltk/security/advisories/GHSA-8mgp-746c-j5xp

Vendor Advisories for CVE-2026-81726(1)

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
pipnltk—ghsa

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
nltk3.10.0-1 ... 3.9.3-1 (9 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
nltk3.10.0-1 ... 3.9.3-1 (6 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
nltk3.10.0-1 ... 3.9.3-1 (6 versions)
  • every version on: no fix on record
—
PyPI(1)
PackageVulnerable rangeFix by version rangeDependents
nltk0.8 ... 3.9b1 (68 versions)
  • every version through 3.10.3: no fix on record
  • every version up to 3.10.3: fixed in 3.10.3
—

Weakness Classification(3)

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

Data Freshness Timeline

(refreshed 20× in last 7d / 102× 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 170 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 70 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-13 16:35 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  2. 2026-10-12 16:35 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  3. 2026-10-12 16:00 UTCEG score recompute
  4. 2026-10-12 16:00 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  5. 2026-10-12 14:56 UTCEG score recompute
  6. 2026-10-11 19:20 UTCEG score recompute
  7. 2026-10-11 16:36 UTCEG score recompute
  8. 2026-10-11 13:54 UTCEG score recompute
  9. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  10. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  11. 2026-10-10 15:12 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  12. 2026-10-10 01:54 UTCEG score recompute
  13. 2026-10-10 01:54 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  14. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  15. 2026-10-09 03:04 UTCEG score recompute
  16. 2026-10-09 03:04 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  17. 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  18. 2026-10-08 01:19 UTCEG score recompute
  19. 2026-10-08 01:19 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  20. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  21. 2026-10-07 02:36 UTCEG score recompute
  22. 2026-10-07 02:36 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  23. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  24. 2026-10-06 13:46 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  25. 2026-10-06 00:53 UTCEG score recompute
Show 75 more
  1. 2026-10-06 00:53 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  2. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  3. 2026-10-05 08:29 UTCEG score recompute
  4. 2026-10-05 08:29 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  5. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  6. 2026-10-04 19:38 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  7. 2026-10-04 04:03 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  8. 2026-10-03 15:13 UTCEG score recompute
  9. 2026-10-03 15:13 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  10. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  11. 2026-10-03 00:29 UTCEG score recompute
  12. 2026-10-03 00:29 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  13. 2026-10-02 17:57 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  14. 2026-10-02 10:26 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  15. 2026-10-01 21:36 UTCEG score recompute
  16. 2026-10-01 21:35 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  17. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  18. 2026-10-01 08:44 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  19. 2026-09-30 19:54 UTCEG score recompute
  20. 2026-09-30 19:54 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  21. 2026-09-30 15:04 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  22. 2026-09-30 05:00 UTCEG score recompute
  23. 2026-09-30 05:00 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  24. 2026-09-29 12:16 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  25. 2026-09-28 22:21 UTCEG score recompute
  26. 2026-09-28 22:21 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  27. 2026-09-28 13:52 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  28. 2026-09-28 09:15 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  29. 2026-09-27 20:25 UTCEG score recompute
  30. 2026-09-27 20:25 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  31. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  32. 2026-09-27 07:35 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  33. 2026-09-26 18:43 UTCEG score recompute
  34. 2026-09-26 18:43 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  35. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  36. 2026-09-25 17:05 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  37. 2026-09-25 04:14 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  38. 2026-09-24 15:24 UTCEG score recompute
  39. 2026-09-24 15:24 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  40. 2026-09-24 14:04 UTCEPSS rescoreEPSS 0.3% · 24th percentile
  41. 2026-09-24 02:15 UTCEG score recompute
  42. 2026-09-24 02:15 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  43. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  44. 2026-09-23 13:24 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  45. 2026-09-23 00:31 UTCEG score recompute
  46. 2026-09-23 00:31 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  47. 2026-09-22 16:01 UTCEPSS rescoreEPSS 0.3% · 17th percentile
  48. 2026-09-22 11:40 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  49. 2026-09-21 22:50 UTCEG score recompute
  50. 2026-09-21 22:50 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  51. 2026-09-21 21:09 UTCEPSS rescoreEPSS 0.3% · 17th percentile
  52. 2026-09-21 10:00 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  53. 2026-09-20 21:10 UTCEG score recompute
  54. 2026-09-20 21:10 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  55. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  56. 2026-09-20 08:20 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  57. 2026-09-19 18:13 UTCEG score recompute
  58. 2026-09-19 18:13 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  59. 2026-09-19 05:22 UTCEG score recompute
  60. 2026-09-19 05:22 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  61. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  62. 2026-09-18 16:31 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  63. 2026-09-18 03:37 UTCEG score recompute
  64. 2026-09-18 03:37 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  65. 2026-09-17 14:47 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  66. 2026-09-17 01:56 UTCEG score recompute
  67. 2026-09-17 01:56 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  68. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.3% · 17th percentile
  69. 2026-09-16 13:05 UTCEG score recompute
  70. 2026-09-16 13:05 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  71. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.3% · 17th percentile
  72. 2026-09-16 00:15 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  73. 2026-09-15 11:23 UTCEG score recompute
  74. 2026-09-15 11:23 UTCGHSA enrichmentGHSA-8mgp-746c-j5xp · GitHub severity HIGH · GitHub CVSS 7.0
  75. 2026-09-15 03:12 UTCEPSS rescoreEPSS 0.3% · 17th percentile

Related CVEs(same product + same CWE)

Frequently asked(5)

What is CVE-2026-81726?
CVE-2026-81726 is a high-severity vulnerability; its CVE record was published on August 27, 2026. NLTK through 3.10.3 contains a path traversal vulnerability in model-artifact APIs that bypass pathsec enforcement by using raw file operations on caller-controlled paths. Attackers can read or write files outside allowed sandbox roots through TransitionParser, AveragedPerceptron, PerceptronTagger,…
When was CVE-2026-81726 made public?
CVE-2026-81726 was made public on August 12, 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 August 27, 2026. EchelonGraph's copy of the record carries a last-modified date of August 31, 2026; the record at its source may have been updated since.
Is CVE-2026-81726 actively exploited?
CVE-2026-81726 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (25th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-81726?
CVE-2026-81726 has a CVSS base score of 7.0 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-81726?
A fix for CVE-2026-81726 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-81726 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-81726

Explore →

Is Your Infrastructure Affected by CVE-2026-81726?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Book a Demo →Browse All CVEs