Skip to content
Fencer Intel
medium 6.3

CVE-2026-15699 json

spencermountain compromise Public Root API extend.js nlp.extend prototype pollution

published 3mo ago modified 16d ago also EUVD-2026-43743

cvss
6.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 39%
public exploits
0
none known

Summary

A vulnerability was identified in spencermountain compromise up to 14.15.1. Affected is the function nlp.extend of the file src/API/extend.js of the component Public Root API. The manipulation of the argument plugin leads to improperly controlled modification of object prototype attributes. Remote exploitation of the attack is possible. The exploit is publicly available and might be used. The identifier of the patch is b4644ab7179700df0607521f61c1ee9b5f78d89d. Applying a patch is the recommended action to fix this issue. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.

Patch / fix

Is CVE-2026-15699 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
3mo ago

Exploit prediction

0.45% chance of exploitation in the next 30 days, higher than 39% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/spencermountain/compromise/issues/1208 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:O/RC:C
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:O/RC:C
CNA 2.0 6.5 AV:N/AC:L/Au:S/C:P/I:P/A:P/E:POC/RL:OF/RC:C
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

  • spencermountain compromise

Classification

Weakness
  • CWE-1321 Improperly Controlled Modification of Object Prototype Attributes
  • CWE-94 Improper Control of Generation of Code

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.