Security readout for executives and security teams
Plain-English summary
Bosch B426 firmware sent user passwords in clear text when HTTP was used. Someone positioned on the network path could capture those credentials and potentially use them to access the device or related systems. Bosch stated the issue would be fixed starting with firmware 3.11.5.
Executive priority
Treat this as a high-priority remediation where Bosch B426 devices are present. The business risk is credential theft leading to unauthorized access, not broad internet-scale exploitation based on the supplied evidence.
Technical view
CVE-2021-23846 is a CWE-319 cleartext transmission flaw in Bosch B426 firmware. Affected listed versions are 03.01.0004, 03.02.002, 03.05.0003, and 03.03.0009. CVSS 3.1 is 8.8 with network attack vector, low complexity, no privileges, user interaction required, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is likely limited to environments running the listed Bosch B426 firmware versions where users access the device over HTTP. Risk increases on shared, untrusted, or poorly segmented networks where a man-in-the-middle position is plausible.
Exploitation context
The source bundle does not report active exploitation, and KEV status is false. The described attack requires a network-path position and user interaction involving HTTP use. No exploit code or public exploitation evidence is provided in the supplied sources.
Researcher notes
The key evidence is cleartext password transmission over HTTP in specific Bosch B426 firmware versions. Bosch identifies firmware 3.11.5 as the fix point. Evidence is incomplete on deployment prevalence, default protocol behavior, and any compensating controls.
Mitigation direction
- Upgrade affected Bosch B426 firmware to version 3.11.5 or later per Bosch guidance.
- Stop using HTTP access paths; use vendor-supported encrypted access where available.
- Restrict device access to trusted administrative networks during remediation.
- Assess whether credentials used over HTTP need rotation under incident procedures.
- Review the Bosch advisory for any product-specific operational guidance.
Validation and detection
- Inventory Bosch B426 firmware versions and flag the listed affected releases.
- Confirm whether users or integrations access the device using HTTP.
- Verify upgraded devices report firmware 3.11.5 or later.
- Review network segmentation around affected devices.
- Check authentication logs for suspicious access after possible HTTP credential exposure.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-319: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCredential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-23846 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 8.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H2.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
8.8HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://psirt.bosch.com/security-advisories/bosch-sa-196933-bt.htmlCVE reference · x_refsource_CONFIRM
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Cleartext Transmission of Sensitive Information
Cleartext Transmission of Sensitive Information represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.