high
8.1
CWE
613
Advisory Published
Updated

CVE-2021-34739: Cisco Small Business Series Switches Session Credentials Replay Vulnerability

First published: Thu Nov 04 2021(Updated: )

A vulnerability in the web-based management interface of multiple Cisco Small Business Series Switches could allow an unauthenticated, remote attacker to replay valid user session credentials and gain unauthorized access to the web-based management interface of an affected device. This vulnerability is due to insufficient expiration of session credentials. An attacker could exploit this vulnerability by conducting a man-in-the-middle attack against an affected device to intercept valid session credentials and then replaying the intercepted credentials toward the same device at a later time. A successful exploit could allow the attacker to access the web-based management interface with administrator privileges.

Credit: ykramarz@cisco.com

Affected SoftwareAffected VersionHow to fix
Cisco SF250-24 Firmware<=2.5
Cisco SF250-24
Cisco SF250-24P Firmware<=2.5
Cisco SF250-24P Firmware
Cisco SF250-48 Firmware<=2.5
Cisco SF250-48
Cisco sf250-48hp firmware<=2.5
Cisco sf250-48hp firmware
Cisco SF250-08 Firmware<=2.5
Cisco SF250-08
Cisco SF250-08HP<=2.5
Cisco SF250-08HP
Cisco sf250-10p<=2.5
Cisco sf250-10p firmware
Cisco SF250-18 Firmware<=2.5
Cisco SF250-18 Firmware
Cisco SF250-26 Firmware<=2.5
Cisco SF250-26 Firmware
Cisco SF250-26HP Firmware<=2.5
Cisco SF250-26HP Firmware
Cisco SF250-26P Firmware<=2.5
Cisco SF250-26P
Cisco SF250-50P Firmware<=2.5
Cisco SF250-50P Firmware
Cisco SF250-50HP Firmware<=2.5
Cisco SF250-50HP Firmware
Cisco SF250-50P Firmware<=2.5
Cisco SF250-50P Firmware
Cisco SF250X-24 Firmware<=2.5
Cisco SF250X-24
Cisco SF250X-24P Firmware<=2.5
Cisco SF250X-24P Firmware
Cisco SF250X-48 Firmware<=2.5
Cisco SF250X-48 Firmware
Cisco SF250X-48P Firmware<=2.5
Cisco SF250X-48P Firmware
Cisco SF350-08 Firmware<=2.5
Cisco SF350-08 Firmware
Cisco SF350-24 Firmware<=2.5
Cisco SF350-24
Cisco SF350-24MP Firmware<=2.5
Cisco SF350-24
Cisco SF350-24P Firmware<=2.5
Cisco SF350-24P
Cisco SF350-48 Firmware<=2.5
Cisco SF350-48P Firmware
Cisco SF350-8MP Firmware<=2.5
Cisco SF350-8MP Firmware
Cisco SF350-48P Firmware<=2.5
Cisco SF350-48P Firmware
Cisco SF352-08P Firmware<=2.5
Cisco SF352-08
Cisco SF352-08MP Firmware<=2.5
Cisco SF352-08MP Firmware
Cisco SF352-08P Firmware<=2.5
Cisco SF352-08P Firmware
Cisco SF350-8PD Firmware<=2.5
Cisco SF350-8PD
Cisco SF350-10 Firmware<=2.5
Cisco SF350-10 Firmware
Cisco SG350-10MP Firmware<=2.5
Cisco SF350-10MP
Cisco SF350-10P Firmware<=2.5
Cisco SF350-10P
Cisco SF350-10SFP Firmware<=2.5
Cisco SF350-10SFP
Cisco SF350-20 Firmware<=2.5
Cisco SF350-20 Firmware
Cisco SF350-28 Firmware<=2.5
Cisco SF350-28 Firmware
Cisco SF350-28MP Firmware<=2.5
Cisco SF350-28MP
Cisco SF350-28P Firmware<=2.5
Cisco SF350-28P Firmware
Cisco SF350-28SFP<=2.5
Cisco SF350-28SFP
Cisco SF350-52 Firmware<=2.5
Cisco SG350-52
Cisco SF350-52MP Firmware<=2.5
Cisco SF350-52MP
Cisco SF350-52P Firmware<=2.5
Cisco SF350-52P Firmware
Cisco SF355-10P Firmware<=2.5
Cisco SG355-10P
Cisco SG350X-8PMD Firmware<=2.5
Cisco SG350X-8PMD Firmware
Cisco SG350X-12PMV Firmware<=2.5
Cisco SG350X-12PMV
Cisco SG350X-24 Firmware<=2.5
Cisco SG350X-24 Firmware
Cisco SG350X-24 Firmware<=2.5
Cisco SG350X-24PV
Cisco SG350X-24MP Firmware<=2.5
Cisco SG350X-24MP
Cisco SG350X-24 Firmware<=2.5
Cisco SG350X-24PD Firmware
Cisco SG350X-24 Firmware<=2.5
Cisco SG350X-24PV
Cisco SG350X-48 Firmware<=2.5
Cisco SG350X-48
Cisco SG350X-48P Firmware<=2.5
Cisco SG350X-48P Firmware
Cisco SG350X-48MP Firmware<=2.5
Cisco SG350X-48MP Firmware
Cisco SG350X-48PV Firmware<=2.5
Cisco SG350X-48PV
Cisco SG350XG-2F10 Firmware<=2.5
Cisco SG350XG-2F10
Cisco SG350XG-24F Firmware<=2.5
Cisco SG350XG-24F Firmware
Cisco SG350XG-24T Firmware<=2.5
Cisco SG350XG-24T Firmware
Cisco SG350XG-48T Firmware<=2.5
Cisco SG350XG-48T Firmware
Cisco SX350X-08 Firmware<=2.5
Cisco SX350X-08 Firmware
Cisco SX350X-12<=2.5
Cisco SX350X-12
Cisco SX350X-24F Firmware<=2.5
Cisco SX350X-24F
Cisco SX350X-24 Firmware<=2.5
Cisco SX350X-24
Cisco SX350X-52 Firmware<=2.5
Cisco SX350X-52 Firmware
Cisco SF550X-24 Firmware<=2.5
Cisco SF550X-24 Firmware
Cisco SF550X-24P Firmware<=2.5
Cisco SF550X-24P
Cisco SF550X-24MP Firmware<=2.5
Cisco SF550X-24MP
Cisco SF550X-48 Firmware<=2.5
Cisco SF550X-48
Cisco SF550X-48P Firmware<=2.5
Cisco SG550X-48P
Cisco SG550X-48MP Firmware<=2.5
Cisco SF550X-48MP
Cisco SG550X-24 Firmware<=2.5
Cisco SG550X-24 Firmware
Cisco SG550X-24P Firmware<=2.5
Cisco SG550X-24P Firmware
Cisco SG550X-24MP Firmware<=2.5
Cisco SG550X-24MP
Cisco SG550X-24MPP Firmware<=2.5
Cisco SG550X-24MPP
Cisco SG550X-48MP Firmware<=2.5
Cisco SG550X-48T
Cisco SG550X-48P Firmware<=2.5
Cisco SG550X-48P
Cisco SG550X-48MP Firmware<=2.5
Cisco SG550X-48MP
Cisco SG550XG-8F8T firmware<=2.5
Cisco SG500XG-8F8T Firmware
Cisco SG550XG-24F Firmware<=2.5
Cisco SG550XG-24F
Cisco SG550XG-24T<=2.5
Cisco SG550XG-24T
Cisco SG550XG-48T Firmware<=2.5
Cisco SG550XG-48T Firmware
Cisco SX550X-12F Firmware<=2.5
Cisco SX550X-12F Firmware
Cisco SX550X-16FT Firmware<=2.5
Cisco SX550X-16FT
Cisco SX550X-24FT Firmware<=2.5
Cisco SX550X-24FT
Cisco SX550X-24F Firmware<=2.5
Cisco SX550X-24F Firmware
Cisco SX550X-24FT Firmware<=2.5
Cisco SX550X-24
Cisco SX550X-52 Firmware<=2.5
Cisco SX550X-52
Cisco CBS250-8T-D Firmware<=3.1
Cisco CBS250-8T-D Firmware
Cisco CBS250-8PP-D<=3.1
Cisco CBS250-8PP-D
Cisco CBS250-8T-E-2G Firmware<=3.1
Cisco CBS250-8T-E-2G Firmware
Cisco CBS250-8PP-E-2G Firmware<=3.1
Cisco CBS250-8PP-E-2G Firmware
Cisco cbs250-8p-e-2g firmware<=3.1
Cisco CBS250-8P-E-2G
Cisco CBS250-8FP-E-2G<=3.1
Cisco cbs250-8fp-e-2g firmware
Cisco CBS250-16T-2G Firmware<=3.1
Cisco CBS250-16T-2G
Cisco CBS250-16P-2G<=3.1
Cisco cbs250-16p-2g firmware
Cisco CBS250-24T-4G Firmware<=3.1
Cisco CBS250-24T-4G
Cisco CBS250-24PP-4G Firmware<=3.1
Cisco CBS250-24PP-4G
Cisco CBS250-24P-4G Firmware<=3.1
Cisco CBS250-24P-4G Firmware
Cisco CBS250-24FP-4G Firmware<=3.1
Cisco CBS250-24FP-4X
Cisco CBS250-48T-4G Firmware<=3.1
Cisco CBS250-48T-4G
Cisco CBS250-48PP-4G Firmware<=3.1
Cisco CBS250-48PP-4G
Cisco CBS250-48P-4G Firmware<=3.1
Cisco CBS250-48P-4G Firmware
Cisco CBS250-24T-4X Firmware<=3.1
Cisco CBS250-24T-4X Firmware
Cisco CBS250-24P-4X Firmware<=3.1
Cisco CBS250-24P-4X
Cisco CBS250-24FP-4X Firmware<=3.1
Cisco CBS250-24FP-4X
Cisco CBS250-48T-4X Firmware<=3.1
Cisco CBS250-48T-4X
Cisco CBS250-48P-4X<=3.1
Cisco CBS250-48P-4X
Cisco CBS350-8T-E-2G Firmware<=3.1
Cisco CBS350-8T-E-2G Firmware
Cisco CBS350-8P-2G Firmware<=3.1
Cisco CBS350-8P-2G Firmware
Cisco cbs350-8p-e-2g firmware<=3.1
Cisco cbs350-8p-e-2g firmware
Cisco CBS350-8FP-2G Firmware<=3.1
Cisco CBS350-8FP-2G Firmware
Cisco CBS350-8FP-E-2G Firmware<=3.1
Cisco CBS350-8FP-E-2G Firmware
Cisco CBS350-8S-E-2G<=3.1
Cisco CBS350-8S-E-2G
Cisco CBS350-16T-2G Firmware<=3.1
Cisco CBS350-16T-2G Firmware
Cisco CBS350-16T-E-2G<=3.1
Cisco CBS350-16T-E-2G
Cisco CBS350-16P-2G<=3.1
Cisco CBS350-16P-2G
Cisco CBS350-16P-E-2G Firmware<=3.1
Cisco CBS350-16P-E-2G Firmware
Cisco CBS350-16FP-2G Firmware<=3.1
Cisco CBS350-16FP-2G Firmware
Cisco CBS350-24T-4G Firmware<=3.1
Cisco CBS350-24T-4G
Cisco CBS350-24P-4G Firmware<=3.1
Cisco CBS350-24P-4G Firmware
Cisco CBS350-24FP-4G Firmware<=3.1
Cisco CBS350-24FP-4G
Cisco CBS350-24S-4G Firmware<=3.1
Cisco CBS350-24S-4G
Cisco CBS350-48T-4G Firmware<=3.1
Cisco CBS350-48T-4G
Cisco CBS350-48P-4G<=3.1
Cisco CBS350-48P-4G
Cisco CBS350-48FP-4G Firmware<=3.1
Cisco CBS350-48FP-4G Firmware
Cisco cbs350-24t-4x firmware<=3.1
Cisco CBS350-24T-4X
Cisco CBS350-24P-4X Firmware<=3.1
Cisco CBS350-24P-4X
Cisco CBS350-24FP-4X Firmware<=3.1
Cisco CBS350-24FP-4X
Cisco CBS350-48T-4X Firmware<=3.1
Cisco CBS350-48T-4X Firmware
Cisco CBS350-48P-4X Firmware<=3.1
Cisco CBS350-48P-4X
Cisco CBS350-48FP-4X<=3.1
Cisco CBS350-48FP-4X
Cisco CBS350-8MG-2X Firmware<=3.1
Cisco CBS350-8MG-2X Firmware
Cisco CBS350-8MG-2X Firmware<=3.1
Cisco CBS350-8MG-2X Firmware
Cisco CBS350-24MGPA-4X Firmware<=3.1
Cisco CBS350-24MG-4X
Cisco CBS350-12NP-4X<=3.1
Cisco CBS350-12NP-4X
Cisco CBS350-24NGP-4X Firmware<=3.1
Cisco CBS350-24NGP-4X Firmware
Cisco CBS350-48NGP-4X Firmware<=3.1
Cisco CBS350-48NGP-4X Firmware
Cisco CBS350-8XT Firmware<=3.1
Cisco CBS350-8XT
Cisco CBS350-12XS Firmware<=3.1
Cisco CBS350-12XS Firmware
Cisco CBS350-12XT Firmware<=3.1
Cisco CBS350-12XT Firmware
Cisco CBS350-16XTS Firmware<=3.1
Cisco CBS350-16XT
Cisco CBS350-24XS Firmware<=3.1
Cisco CBS350-24XS
Cisco CBS350-24XT Firmware<=3.1
Cisco CBS350-24XT Firmware
Cisco CBS350-24XT<=3.1
Cisco CBS350-24XT
Cisco CBS350-48XT-4X Firmware<=3.1
Cisco CBS350-48XT-4X Firmware
Cisco ESW2-350G-52 Firmware<=2.5
Cisco ESW2-350G-52
Cisco ESW2-350G-52DC<=2.5
Cisco ESW2-350G-52DC
Cisco ESW2-550X-48 Firmware<=2.5
Cisco ESW2-550X-48
Cisco ESW2-550X-48DC Firmware<=2.5
Cisco ESW2-550X-48DC
Cisco SF200-24 Firmware
Cisco SF200-24P
Cisco SF200-24P Firmware
Cisco SF200-24P
Cisco SF200-24FP Firmware
Cisco SF200-24FP
Cisco SF200-48 Firmware
Cisco SF200-48 Firmware
Cisco SF200-48P Firmware
Cisco SF200-48P Firmware
Cisco SG200-08 Firmware
Cisco SG200-08 Firmware
Cisco SG200-08P Firmware
Cisco SG200-08P
Cisco SG200-10FP Firmware
Cisco SG200-10FP Firmware
Cisco SG200-18 Firmware
Cisco SG200-18 Firmware
Cisco SG200-26FP Firmware
Cisco SG200-26P Firmware
Cisco SG200-26P Firmware
Cisco SG200-26P Firmware
Cisco SG200-26FP Firmware
Cisco SG200-26FP Firmware
Cisco SG200-50P Firmware
Cisco SG200-50FP
Cisco SG200-50P Firmware
Cisco SG200-50P Firmware
Cisco SG200-50FP Firmware
Cisco SG200-50FP
Cisco SF300-08 Firmware=1.4.11.02
Cisco SF300-08 Firmware
Cisco SF302-08 Firmware=1.4.11.02
Cisco SF302-08
Cisco SF302-08P Firmware=1.4.11.02
Cisco SF302-08P Firmware
Cisco SF302-08PP Firmware=1.4.11.02
Cisco SF302-08PP Firmware
Cisco SF302-08MP Firmware=1.4.11.02
Cisco SF302-08MP
Cisco SF302-08MPP Firmware=1.4.11.02
Cisco SF302-08MPP
Cisco SF300-24P Firmware=1.4.11.02
Cisco SF300-24
Cisco SF300-24P=1.4.11.02
Cisco SF300-24P
Cisco SF300-24PP Firmware=1.4.11.02
Cisco SF300-24PP
Cisco sf300-24mp firmware=1.4.11.02
Cisco SF300-24MP
Cisco SF300-48P Firmware=1.4.11.02
Cisco SF300-48
Cisco SF300-48P Firmware=1.4.11.02
Cisco SF300-48P Firmware
Cisco SF300-48PP Firmware=1.4.11.02
Cisco SF300-48PP Firmware
Cisco SG300-10 Firmware=1.4.11.02
Cisco SG300-10
Cisco SG300-10SFP Firmware=1.4.11.02
Cisco SG300-10SFP Firmware
Cisco SG300-10P Firmware=1.4.11.02
Cisco SG300-10P
Cisco SG300-10PP Firmware=1.4.11.02
Cisco SG300-10PP Firmware
Cisco SG300-10MP Firmware=1.4.11.02
Cisco SG300-10MP Firmware
Cisco SG300-10MPP Firmware=1.4.11.02
Cisco SG300-10MPP Firmware
Cisco SG300-20 Firmware=1.4.11.02
Cisco SG300-20 Firmware
Cisco SG300-28 Firmware=1.4.11.02
Cisco SG300-28
Cisco SG300-28P Firmware=1.4.11.02
Cisco SG300-28P
Cisco SG300-28PP Firmware=1.4.11.02
Cisco SG300-28PP
Cisco SG300-28MP=1.4.11.02
Cisco SG300-28MP
Cisco SG300-52 Firmware=1.4.11.02
Cisco SG300-52
Cisco SG300-52P Firmware=1.4.11.02
Cisco SG300-52P
Cisco SG300-52MP Firmware=1.4.11.02
Cisco SG300-52MP
Cisco SG300-28SFP Firmware=1.4.11.02
Cisco SG300-28SFP
Cisco SF500-24>=2.5.5.0<2.5.8.12
Cisco SF500-24MP
Cisco SF500-24P>=2.5.5.0<2.5.8.12
Cisco SF500-24P Firmware
Cisco SF500-24MP Firmware>=2.5.5.0<2.5.8.12
Cisco SF500-24MP Firmware
Cisco SF500-48P Firmware>=2.5.5.0<2.5.8.12
Cisco SF500-48 Firmware
Cisco SF500-48P Firmware>=2.5.5.0<2.5.8.12
Cisco SF500-48 Firmware
Cisco SF500-48MP>=2.5.5.0<2.5.8.12
Cisco SF500-48MP Firmware
Cisco SG500-28>=2.5.5.0<2.5.8.12
Cisco SG500-28PP Firmware
Cisco SG500-28P>=2.5.5.0<2.5.8.12
Cisco SG500-28P
Cisco SG500-28PP Firmware>=2.5.5.0<2.5.8.12
Cisco SG500-28MPP Firmware
Cisco SG500-52P>=2.5.5.0<2.5.8.12
Cisco SG500-52 Firmware
Cisco SG500-52P>=2.5.5.0<2.5.8.12
Cisco SG500-52P
Cisco SG500-52MP>=2.5.5.0<2.5.8.12
Cisco SG500-52
Cisco SG500X-24>=2.5.5.0<2.5.8.12
Cisco SG500X-24P
Cisco SG500X-24P>=2.5.5.0<2.5.8.12
Cisco SG500X-24P
Cisco SG500X-24MPP>=2.5.5.0<2.5.8.12
Cisco SG500X-24MPP Firmware
Cisco SG500X-48>=2.5.5.0<2.5.8.12
Cisco SG500X-48MP Firmware
Cisco SG500X-48P>=2.5.5.0<2.5.8.12
Cisco SG500X-48P
Cisco SG500X-48MP Firmware>=2.5.5.0<2.5.8.12
Cisco SG500X-48
Cisco SG500XG-8F8T Firmware>=2.5.5.0<2.5.8.12
Cisco SG500XG-8F8T Firmware

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-34739?

    The severity of CVE-2021-34739 is rated as high due to its potential for unauthorized access to network devices.

  • How do I fix CVE-2021-34739?

    To fix CVE-2021-34739, upgrade the affected Cisco Small Business Switches to the latest firmware that addresses the vulnerability.

  • Which devices are affected by CVE-2021-34739?

    CVE-2021-34739 affects multiple Cisco Small Business Series Switches, including SF250, SF350, and others with firmware versions up to 2.5.

  • Is there a workaround for CVE-2021-34739?

    There are no specific workarounds for CVE-2021-34739; however, disabling remote management access can help mitigate the risk.

  • When was CVE-2021-34739 disclosed?

    CVE-2021-34739 was disclosed in July 2021 as part of Cisco's security advisories.

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