CVE-2026-78682

HIGHPre-NVD 7.57.5—
EchelonGraph scoreHIGH confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-08-25. a secondary CVSS source baseline 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Elevated
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.5Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

NLTK before 3.10.3 contains a server-side request forgery vulnerability in nltk.pathsec.urlopen (and callers nltk.data.load, nltk.downloader.Downloader.index/download) when an HTTP proxy is configured. pathsec.urlopen validates the requested hostname locally, but proxy-handler inheritance disables the safe HTTP/HTTPS handlers so the actual fetch is performed by the proxy against a destination that is never re-validated. An attacker can supply a validated public URL that the proxy forwards to an internal loopback-only service, allowing disclosure of internal HTTP resources, loading of forged downloader indexes, and installation of attacker-chosen package content.

CVSS v3
7.5
EG Score
7.5(high)
EG Risk
65(Attend)
EG Risk 65/100SSVC: Attend

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
Severity75% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
0%
EPSS %ILE
17%
KEV
Not listed

Published

August 25, 2026

Last Modified

August 31, 2026

Advisory Details (2)

Auto-updated Aug 25, 2026
🔬 Proof of concept available. Patch available. Sources: github.
generic

NLTK before 3.10.3 SSRF Protection Bypass via Proxy | Advisories | VulnCheck

https://www.vulncheck.com/advisories/nltk-before-ssrf-protection-bypass-via-proxy
github Patch Available🟡 PoC Available

pathsec SSRF protection can be bypassed when a proxy is configured · Advisory · nltk/nltk · GitHub

https://github.com/nltk/nltk/security/advisories/GHSA-6ww7-3frv-cqxh

Vendor Advisories for CVE-2026-78682(1)

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

Affected Packages

(4 across 4 ecosystems)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
nltk3.10.0-1 ... 3.9.3-1 (9 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
nltk3.10.0-1 ... 3.9.3-1 (6 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
nltk3.10.0-1, 3.10.1-1, 3.9.1-2, 3.9.2-1, 3.9.3-13.10.3-1—
PyPI(1)
PackageVulnerable rangeFixed inDependents
nltk0.8 ... 3.9b1 (68 versions)3.10.3—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 11× in last 7d / 71× 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.

  1. 2026-09-19 02:30 UTCEG score recompute
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-18 02:35 UTCEG score recompute
  4. 2026-09-16 14:15 UTCEG score recompute
  5. 2026-09-16 14:08 UTCEPSS rescore
  6. 2026-09-16 05:15 UTCEPSS rescore
  7. 2026-09-15 13:38 UTCEG score recompute
  8. 2026-09-15 03:12 UTCEPSS rescore
  9. 2026-09-15 03:12 UTCEPSS rescore
  10. 2026-09-14 01:31 UTCEG score recompute
  11. 2026-09-13 01:37 UTCEG score recompute
  12. 2026-09-12 01:43 UTCEG score recompute
  13. 2026-09-11 14:53 UTCEPSS rescore
  14. 2026-09-11 14:53 UTCEPSS rescore
  15. 2026-09-11 13:46 UTCEG score recompute
  16. 2026-09-10 13:52 UTCEG score recompute
  17. 2026-09-09 01:19 UTCEG score recompute
  18. 2026-09-08 22:01 UTCEPSS rescore
  19. 2026-09-07 20:34 UTCEG score recompute
  20. 2026-09-06 20:37 UTCEG score recompute
  21. 2026-09-06 13:48 UTCEPSS rescore
  22. 2026-09-05 20:42 UTCEG score recompute
  23. 2026-09-04 20:49 UTCEG score recompute
  24. 2026-09-04 08:41 UTCEG score recompute
  25. 2026-09-04 05:07 UTCEPSS rescore
Show 46 more
  1. 2026-09-02 20:45 UTCEG score recompute
  2. 2026-09-02 14:12 UTCEPSS rescore
  3. 2026-09-02 07:15 UTCGHSA enrichment
  4. 2026-09-02 07:13 UTCGHSA enrichment
  5. 2026-09-01 19:12 UTCEG score recompute
  6. 2026-09-01 19:12 UTCGHSA enrichment
  7. 2026-09-01 13:54 UTCEPSS rescore
  8. 2026-09-01 07:11 UTCEG score recompute
  9. 2026-09-01 07:11 UTCGHSA enrichment
  10. 2026-09-01 04:40 UTCEPSS rescore
  11. 2026-09-01 04:40 UTCEPSS rescore
  12. 2026-08-31 19:14 UTCGHSA enrichment
  13. 2026-08-31 19:02 UTCGHSA enrichment
  14. 2026-08-31 07:05 UTCEG score recompute
  15. 2026-08-31 07:05 UTCGHSA enrichment
  16. 2026-08-30 19:18 UTCEPSS rescore
  17. 2026-08-30 19:17 UTCEPSS rescore
  18. 2026-08-30 19:05 UTCGHSA enrichment
  19. 2026-08-30 07:08 UTCEG score recompute
  20. 2026-08-30 07:08 UTCGHSA enrichment
  21. 2026-08-30 01:22 UTCEPSS rescore
  22. 2026-08-29 19:09 UTCGHSA enrichment
  23. 2026-08-29 07:07 UTCEG score recompute
  24. 2026-08-29 07:07 UTCGHSA enrichment
  25. 2026-08-28 21:42 UTCEPSS rescore
  26. 2026-08-28 19:08 UTCGHSA enrichment
  27. 2026-08-28 16:23 UTCGHSA enrichment
  28. 2026-08-28 04:23 UTCGHSA enrichment
  29. 2026-08-27 16:25 UTCEG score recompute
  30. 2026-08-27 16:25 UTCGHSA enrichment
  31. 2026-08-27 14:25 UTCEPSS rescore
  32. 2026-08-27 04:25 UTCGHSA enrichment
  33. 2026-08-26 16:24 UTCEG score recompute
  34. 2026-08-26 16:24 UTCGHSA enrichment
  35. 2026-08-26 14:47 UTCEPSS rescore
  36. 2026-08-26 04:21 UTCGHSA enrichment
  37. 2026-08-25 16:24 UTCEG score recompute
  38. 2026-08-25 16:24 UTCGHSA enrichment
  39. 2026-08-25 15:30 UTCEG score recompute
  40. 2026-08-25 15:30 UTCGHSA enrichment
  41. 2026-08-25 14:16 UTCEG score recompute
  42. 2026-08-25 14:16 UTCGHSA enrichment
  43. 2026-08-25 13:49 UTCEPSS rescore
  44. 2026-08-25 02:19 UTCEG score recompute
  45. 2026-08-25 01:50 UTCEG score recompute
  46. 2026-08-25 01:50 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-78682?
CVE-2026-78682 is a high vulnerability published on August 25, 2026. NLTK before 3.10.3 contains a server-side request forgery vulnerability in nltk.pathsec.urlopen (and callers nltk.data.load, nltk.downloader.Downloader.index/download) when an HTTP proxy is configured. pathsec.urlopen validates the requested hostname locally, but proxy-handler inheritance disables…
When was CVE-2026-78682 disclosed?
CVE-2026-78682 was first published in the National Vulnerability Database on August 25, 2026, with the most recent update on August 31, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-78682 actively exploited?
CVE-2026-78682 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 82.8% of all scored CVEs.
What is the CVSS score of CVE-2026-78682?
CVE-2026-78682 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-78682?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-78682, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-78682

Explore →

Is Your Infrastructure Affected by CVE-2026-78682?

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

Start Free Scan →Browse All CVEs