Sentry Seer vulnerability allows attacker-controlled input to be executed in a privileged environment

published 2026-09-16 last mo. modified 2026-09-18 last mo. also EUVD-2026-80853

cvss: 9.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 52%
public exploits: 0; none known

Sentry Seer is vulnerable to a multi-stage trust-boundary violation that allows unauthenticated attacker-controlled telemetry to become code that is executed by an agent in a privileged automation environment. An external attacker can submit fabricated Sentry events without having access to the victim’s Sentry account, source repository, or infrastructure.

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CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: total
Assessed: last mo. (2026-09-18)

Exploit prediction

0.67% chance of exploitation in the next 30 days, higher than 52% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

Functional Software, Inc. Sentry Seer

Classification

Weakness

CWE-20 Improper Input Validation
CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component
CWE-116 Improper Encoding or Escaping of Output
CWE-94 Improper Control of Generation of Code
CWE-913 Improper Control of Dynamically-Managed Code Resources

References

Sources

CVE List CVE-2026-90999
NVD CVE-2026-90999

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