VulnRadar

Data against noise.

Page generated: 10 Nov 2026, 18:24 UTC

CVE-2021-27878

Read full description

An issue was discovered in Veritas Backup Exec before 21.2. The communication between a client and an Agent requires successful authentication, which is typically completed over a secure TLS communication. However, due to a vulnerability in the SHA Authentication scheme, an attacker is able to gain unauthorized access and complete the authentication process. Subsequently, the client can execute data management protocol commands on the authenticated connection. The attacker could use one of these commands to execute an arbitrary command on the system using system privileges.

CVSS 8.8 (HIGH) KEV: KNOWN CATALOG

Attention and evidence

HYPE SCORE

0.0/10

REALITY · THREAT PRIORITY

8.4/10

General review priority; not probability

Evidence confidence: Exploitation recorded

Why this priority?

Recorded exploitation baseline: +7.00
Technical severity: CVSS 8.8: +1.32
Fresh EPSS: 23.95%: +0.12

General review priority, not probability, victim count or asset-specific risk. A range covers missing CVSS/EPSS inputs within the current evidence state.

Sources: 9 documents and public datasets.

Hype components

Headline sample (25%)

0/100

Press, 30 days (60%)

0/100

Grounded branding (15%)

0/100

HYPE TOTAL0/100

Sources and documents

Google Cloud

Press · 03 Jun 2024, 07:00 · Ransomware Rebounds: Extortion Threat Surges in 2023, Attackers Rely on Publicly Available and Legitimate Tools - Google Cloud

Cyfirma

Press · 10 Aug 2023, 07:00 · RANSOMWARE TRENDS : H1 2023 Part-2 - Cyfirma

GBHackers News

Press · 11 Apr 2023, 07:00 · CISA Urges to Fix Backup Exec Bug Exploited to Deploy Ransomware - GBHackers News

SecurityWeek

Press · 10 Apr 2023, 07:00 · Veritas Vulnerabilities Exploited in Ransomware Attacks Added to CISA ‘Must Patch’ List - SecurityWeek

The Hacker News

Press · 10 Apr 2023, 07:00 · CISA Warns of 5 Actively Exploited Security Flaws: Urgent Action Required - The Hacker News

See all 9 source documents

BleepingComputer

Press · 07 Apr 2023, 07:00 · CISA orders agencies to patch Backup Exec bugs used by ransomware gang - BleepingComputer

BleepingComputer

Press · 04 Apr 2023, 07:00 · ALPHV ransomware exploits Veritas Backup Exec bugs for initial access - BleepingComputer

Google Cloud

Press · 03 Apr 2023, 07:00 · ALPHV Ransomware Affiliate Targets Vulnerable Backup Installations to Gain Initial Access | Mandiant - Google Cloud

Rapid7

Press · 30 Sep 2022, 07:00 · Metasploit Weekly Wrap-Up: Sep. 30, 2022 - Rapid7

Score evolution

● Hype ● Reality

Earlier evidence-support scores are retained in history; this chart shows only the current priority definition.

First record: hype 0.0 · reality 8.4 (2026-11-02 15:12). The curve appears once the score changes.

Public exploit evidence

Public exploit entries / repo candidates

Evidence context and dated references

Reality is general threat/review priority, combining observed exploitation, CVSS severity and fresh EPSS. Evidence confidence is separate. This is not calibrated risk, a victim count or an asset-specific assessment. A range reflects missing numeric inputs.

Evidence in context

Confidence in exploitation evidence: Exploitation recorded
Priority basis: Recorded exploitation; CVSS 8.8; EPSS 24.0%
Attention, last 30 days: 0 distinct story titles; 0 press documents; 0 publisher domains.
Technical potential: network access, low privileges, no user interaction.
Observed activity: Exploitation recorded in CISA KEV.
Known scale: Not quantified.
Evidence confidence basis: Trusted exploitation confirmation

Score evaluated: 2026-11-05 13:58:25.853394+00:00 · EPSS snapshot: 2026-11-05T12:03:04Z

Source event timeline

Published

01 Mar 2021, 21:49

First press mention

30 Sep 2022, 07:00

Added to the CISA KEV catalog

07 Apr 2023, 00:00

Latest press mention

03 Jun 2024, 07:00

Score calculated

05 Nov 2026, 13:58