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Fencer Intel
medium 6.3

CVE-2026-1977 json

isaacwasserman mcp-vegalite-server visualize_data eval code injection

published 9mo ago modified 4mo ago also EUVD-2026-5601

cvss
6.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 19%
public exploits
0
none known

Summary

A security vulnerability has been detected in isaacwasserman mcp-vegalite-server up to 16aefed598b8cd897b78e99b907f6e2984572c61. Affected by this vulnerability is the function eval of the component visualize_data. Such manipulation of the argument vegalite_specification leads to code injection. The attack may be performed from remote. The exploit has been disclosed publicly and may be used. This product utilizes a rolling release system for continuous delivery, and as such, version information for affected or updated releases is not disclosed. The project was informed of the problem early through an issue report but has not responded yet.

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
9mo ago

Exploit prediction

0.27% chance of exploitation in the next 30 days, higher than 19% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/isaacwasserman/mcp-vegalite-server/issues/9 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 5.3 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
CNA 3.1 6.3 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
CNA 3.0 6.3 CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
CNA 2.0 6.5 AV:N/AC:L/Au:S/C:P/I:P/A:P/E:POC/RL:ND/RC:UR
CNA 4.0 2.1 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/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
CNA 3.1 6.3 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
CNA 2.0 6.5 AV:N/AC:L/Au:S/C:P/I:P/A:P

Affected products

  • isaacwasserman mcp-vegalite-server

Classification

Weakness
  • CWE-94 Improper Control of Generation of Code
  • CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.