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CVE-2021-42567 (GCVE-0-2021-42567)

Vulnerability from cvelistv5 – Published: 2021-12-07 21:10 – Updated: 2024-08-04 03:38
VLAI Shadowserver
Summary
Apereo CAS through 6.4.1 allows XSS via POST requests sent to the REST API endpoints.
Severity
6.1 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CWE
  • n/a
Assigner
References
Shadowserver
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: 115ad228-1bed-4b3e-8428-a2dcc48ceace

Vulnerability ID: CVE-2021-42567

Status: Confirmed

Status Updated: 2026-09-06 00:00 UTC

Exploited: Yes

Characteristics
Severity: 61.0
Timestamps
First Seen: 2023-10-23
Asserted: 2023-10-23
Last Seen: 2026-09-06
Scope
Asset Exposure: ['internet-facing']
Notes: Affected: Apereo / CAS | Class: other-software | Severity: Medium (CVSS 6.1) | IoT: no | In CISA KEV: no | Honeypot connections on 2026-09-06: 1
Evidence

Type: Honeypot

Signal: In The Wild Attempts

Confidence: 70%

Source: shadowserver

Details
1D 1
Iot no
Feed Shadowserver Foundation honeypot/exploited-vulnerabilities
Type http-scan
Class other-software
7D Avg 1
Vendor Apereo
30D Avg 0
90D Avg 0
Product CAS
Cisa Kev no
Connections 1
Observation Date 2026-09-06
Vulnerability Class CVSS
Vulnerability Score 6.1
Vulnerability Severity Medium
References
Created: 2026-07-01 05:54 UTC | Updated: 2026-09-08 01:01 UTC
Show details on NVD website
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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