CVE-2021-34741

mediumPriorität · verfolgen · 30EPSS 0.013 · 70. PerzentilEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.29% (70th) EPSS

CVSS 5 · medium

Is it mine?

6 products

Prüfe deine Angriffsfläche

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · bewertet 2026-10-27

A vulnerability in the email scanning algorithm of Cisco AsyncOS software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to perform a denial of service (DoS) attack against an affected device. This vulnerability is due to insufficient input validation of incoming emails. An attacker could exploit this vulnerability by sending a crafted email through Cisco ESA. A successful exploit could allow the attacker to exhaust all the available CPU resources on an affected device for an extended period of time, preventing other emails from being processed and resulting in a DoS condition.

Behebungen

Hersteller-Fix, Mitigation oder Workaround, wie von den Quellen veröffentlicht.

Ein Hersteller-Fix ist verfügbar.

BehobenCisco Secure Emailcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com

cvss

Technischer Schweregrad, 0–10. Eine Zeile je Quelle.

7.5

010

Basiswert 0–10 · höher = schwerwiegender · Vektor überfahren zum Auflösen⚠ Quellen uneinig · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USAusnutzbarkeit 10 · Auswirkung 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USAusnutzbarkeit 3.9 · Auswirkung 3.6

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · psirt@cisco.com USAusnutzbarkeit 3.9 · Auswirkung 3.6

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · Cisco PSIRT US

SSVC

Eine Handlungsentscheidung — aus Ausnutzung und Auswirkung.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

schwächen

Die CWE-Schwächeklassen, zu denen dies gehört.

CWE-770USprimärCWE-20USCWE-770US

betroffene Produkte (6)

Betroffene Produkte und Versionsbereiche.

Cisco Cisco Secure Emailalle Versionencisco_csafUS
Cisco Cisco Email Security Appliance (ESA)≤ n/aenisa_euvdEU
Cisco Systems Inc. AsyncOS≤ 14.0fstec_bduRU
cisco asyncos< 13.0.4nvdUScpe:2.3:o:cisco:asyncos:*:*:*:*:*:*:*:*
cisco asyncos= 13.5.3-010nvdUScpe:2.3:o:cisco:asyncos:*:*:*:*:*:*:*:*
cisco asyncos= 13.7.0-093nvdUScpe:2.3:o:cisco:asyncos:*:*:*:*:*:*:*:*

Advisories (1)

Hersteller- und Ökosystem-Meldungen dazu.

cisco-sa-esa-dos-JOm9ETfOCisco Email Security Appliance Denial of Service Vulnerability2021-11-03csaf · cisco_csafUS
A vulnerability in the email scanning algorithm of Cisco AsyncOS software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to perform a denial of service (DoS) attack against an affected device. This vulnerability is due to insufficient input validation of incoming emails. An attacker could exploit this vulnerability by sending a crafted email through Cisco ESA. A successful exploit could allow the attacker to exhaust all the available CPU resources on an affected device for an extended period of time, preventing other emails from being processed and resulting in a DoS condition. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

auch bekannt als (4)

Weitere Namen und Kennungen dieser Entität.

quellen

Welche Quellen diesen Datensatz belegen und wann.

cnnvd enisa_euvd fstec_bdu cisco_csaf nvd NVD CVE.org MITRE

veröffentlicht 2021-11-04geändert 2026-06-17

verwandt (3,268)

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+3263 weitere

Referenzen (7)

Externe Belege — Patches, Meldungen, Analysen.

scry

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