CVE intelligence and bounded remediation

CVE-2021-34739 — Cisco Sf250-24 Firmware security vulnerability

High CVSS 8.1

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.

Severity
High
CVSS
8.1 (3.1)
Published
2021-11-04
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-613

Affected products

  • cisco / sf250-24_firmware
  • cisco / sf250-24p_firmware
  • cisco / sf250-48_firmware
  • cisco / sf250-48hp_firmware
  • cisco / sf250-08_firmware
  • cisco / sf250-08hp_firmware

Showing 6 representative product identities from 209 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

General vulnerability remediation

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Confirm the affected component, deployment paths, reachable interfaces, and enabled features from inventories and configuration, without probing production destructively.
  • Compare the advisory's affected conditions with the repository lockfiles, build manifests, artifacts, and runtime inventory.
  • Identify data sensitivity, trust boundaries, and privilege level for every confirmed affected deployment.

Remediate safely

  • Apply a vendor-supported fix or remove the affected component or feature; record the selected change and its source in the repository.
  • Update direct and transitive dependency locks, generated artifacts, deployment manifests, and asset inventories together.
  • Add a regression test for the documented unsafe condition using inert inputs and preserve rollback instructions.

Authoritative sources

Complete CVE record and remediation plan

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