Skip to content
Fencer Vulns
critical 9.1

CVE-2026-47731 json

NASA AMMOS Instrument Toolkit: Path traversal resulting in arbitrary file append (can be triggered over the network by unauthenticated attacker)

published 2026-06-05 5 mo ago modified 2026-10-24 15 d ago also GHSA-p462-prxw-mjx4 , PYSEC-2026-265 , EUVD-2026-47011

cvss
9.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.9%
EPSS 0.9% chance of exploitation in 30 days, percentile 59%
public exploits
0
none known

Summary

The AMMOS Instrument Toolkit (Formerly the Bespoke Links to Instruments for Surface and Space (BLISS)) is a Python-based software suite developed to handle Ground Data System (GDS), Electronic Ground Support Equipment (EGSE), commanding, telemetry uplink/downlink, and sequencing for instrument and CubeSat Missions. In versions prior to 2.6.1 and in version 3.1.0, the Binary Stream Capture (BSC) component exposes an unauthenticated HTTP API for dynamically creating packet capture "handlers." Because the code blindly trusts path‑related form fields, a remote client can bypass the configured log root and direct BSC to log to arbitrary filesystem paths (path traversal / directory escape), and append attacker‑controlled data to those files, using the privileges of the`ait-bsc` process. There are two ways for a remote attacker to trigger this. First, if the attacker has access to the network where `ait-bsc` is deployed (a reason for that could be that the ports are publicly accessible), the payloads can be directly sent to the server to trigger the arbitrary file append. This type of attack is demonstrated in `python_poc.py`. Second, even if the attacker does not have direct access to the network because the software is running in a local network, it is possible to exploit this if a bad actor in that network opens an attacker-controlled website (which might be a website created by an attacker, or a third-party website compromised by the attacker). The browser javascript can automatically send the requests necessary to exploit this into the local network. This is even possible if the server is only accessible on `localhost`. This type of attack is demonstrated by `attacker_tcp.py` and `test1.html` (first launch the attacker TCP server, then start a webserver to host `test1.html`, for example using `python3 -m http.server 7000`, and open `test1.html`).This issue affects BSC (Binary Stream Capture) and usage of the ait-bsc server. This impacts AIT-Core versions before 3.1.1, from 2.x before 2.6.1. Users are recommended to upgrade to version 3.1.1 or 2.6.1.

Patch / fix

CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
partial
Assessed
3 mo ago

Exploit prediction

0.89% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • github.com https://github.com/NASA-AMMOS/AIT-Core/security/advisories/GHSA-p462-prxw-mjx4 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 9.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
OSV 3.1 9.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
GitHub 3.1 9.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

Affected packages

ecosystem package affected fixed in
pypi ait-core
>=3.1.0, <3.1.1
<2.6.1
3.1.1
2.6.1

Affected products

  • NASA-AMMOS AIT-Core

Classification

Weakness
  • CWE-22 Improper Limitation of a Pathname to a Restricted Directory

References

Sources

Fencer Vulns 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.