CVE-2021-27877 (GCVE-0-2021-27877)

Vulnerability from cvelistv5 – Published: 2021-03-01 21:49 – Updated: 2025-10-21 23:25
VLAI? CISA KEV
Summary
An issue was discovered in Veritas Backup Exec before 21.2. It supports multiple authentication schemes: SHA authentication is one of these. This authentication scheme is no longer used in current versions of the product, but hadn't yet been disabled. An attacker could remotely exploit this scheme to gain unauthorized access to an Agent and execute privileged commands.
Severity ?
8.2 (High)
CVSS:3.1/AC:L/AV:N/A:N/C:H/I:L/PR:N/S:U/UI:N
CWE
  • n/a
Assigner
References
CISA KEV
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: 4dac3bdf-00b4-4efe-a765-0f70ab838285

Vulnerability ID: CVE-2021-27877

Status: Confirmed

Status Updated: 2023-04-07 00:00 UTC

Exploited: Yes

Timestamps
First Seen: 2023-04-07
Asserted: 2023-04-07
Scope
Notes: KEV entry: Veritas Backup Exec Agent Improper Authentication Vulnerability | Affected: Veritas / Backup Exec Agent | Description: Veritas Backup Exec (BE) Agent contains an improper authentication vulnerability that could allow an attacker unauthorized access to the BE Agent via SHA authentication scheme. | Required action: Apply updates per vendor instructions. | Due date: 2023-04-28 | Known ransomware campaign use (KEV): Known | Notes (KEV): https://www.veritas.com/support/en_US/security/VTS21-001; https://nvd.nist.gov/vuln/detail/CVE-2021-27877
Evidence

Type: Vendor Report

Signal: Successful Exploitation

Confidence: 80%

Source: cisa-kev

Details
Cwes CWE-287
Feed CISA Known Exploited Vulnerabilities Catalog
Product Backup Exec Agent
Due Date 2023-04-28
Date Added 2023-04-07
Vendorproject Veritas
Vulnerabilityname Veritas Backup Exec Agent Improper Authentication Vulnerability
Knownransomwarecampaignuse Known
References
Created: 2026-02-02 13:25 UTC | Updated: 2026-02-06 07:53 UTC
Show details on NVD website
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Sightings

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • 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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