CVE-2026-78680 json
NLTK before 3.10.3 Arbitrary Code Execution via Graphviz dot Binary
published 2026-08-25 2 mo ago modified 2026-10-12 27 d ago also GHSA-6hwm-xvph-95vm , PYSEC-2026-3868 , EUVD-2026-65226
- cvss
- 7.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 7%
- public exploits
- 0
- none known
Summary
NLTK versions before 3.10.3 fail to use validated absolute paths when invoking the Graphviz dot binary in dependencygraph.dot2img and AlignedSent._repr_svg_, allowing attackers to execute arbitrary code by placing a malicious dot binary in the search path or current working directory. Attackers can exploit bare-name binary resolution on Windows via the current working directory or on Unix-like systems via relative PATH entries to execute their binary instead of the legitimate Graphviz tool.
Patch / fix
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- total
- Assessed
- 2 mo ago
Exploit prediction
0.18% chance of exploitation in the next 30 days, higher than 7% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/nltk/nltk/security/advisories/GHSA-6hwm-xvph-95vm referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.5 | CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| CNA | 4.0 | 8.5 | CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| GitHub | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| OSV | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | nltk | <3.10.3 |
3.10.3 |
Affected products
- nltk nltk
Classification
References
-
github.com
/nltk/nltk/commit/1a3cd1764ab3deb084fb66d0ffb4873717659538
web
-
github.com
/nltk/nltk/security/advisories/GHSA-6hwm-xvph-95vm
vendor-advisory, exploit, web
-
vulncheck.com
/advisories/nltk-before-arbitrary-code-execution-via-graphviz-dot-binary
third-party-advisory, web
-
nvd.nist.gov
/vuln/detail/CVE-2026-78680
advisory
-
github.com
/nltk/nltk
package
-
github.com
/nltk/nltk/releases/tag/v3.10.3
web
-
pypi.org
/project/nltk
package
-
github.com
/advisories/GHSA-6hwm-xvph-95vm
advisory
Sources
- CVE List CVE-2026-78680
- GitHub Advisory GHSA-6hwm-xvph-95vm
- NVD CVE-2026-78680
- OSV PYSEC-2026-3868
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