CyberSecBulletin
CVE-2023-35861NVD status: Modified

h12dst-b: Improper Neutralization of Special Elements used in an OS Command

Published Updated By the CyberSecBulletin desk

CVE-2023-35861 is a critical-severity improper neutralization of special elements used in an OS command vulnerability in h12dst-b from Supermicro, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 03.10.35 as the first without the flaw, so updating h12dst-b to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 2.11% chance of exploitation within 30 days, higher than 82% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update h12dst-b to 03.10.35 or a later version.
  2. Update H12dst-b Firmware to 03.10.35 or a later version.
  3. Read the advisory on supermicro.com for workarounds and exact fixed builds.
  4. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Supermicroh12dst-bbefore 03.10.3503.10.35
SupermicroH12dst-b Firmwarebefore 03.10.3503.10.35
SupermicroX13dai-t FirmwareNot specified in the recordNot stated
SupermicroX13ddw-a FirmwareNot specified in the recordNot stated
SupermicroX13deg-oa FirmwareNot specified in the recordNot stated
SupermicroX13deg-oad FirmwareNot specified in the recordNot stated
SupermicroX13deg-pvc FirmwareNot specified in the recordNot stated
SupermicroX13deg-qt FirmwareNot specified in the recordNot stated
SupermicroX13dei FirmwareNot specified in the recordNot stated
SupermicroX13dei-t FirmwareNot specified in the recordNot stated
SupermicroX13dem FirmwareNot specified in the recordNot stated
SupermicroX13det-b FirmwareNot specified in the recordNot stated
SupermicroX13dgu FirmwareNot specified in the recordNot stated
SupermicroX13dsf-a FirmwareNot specified in the recordNot stated
SupermicroX13qeh+ FirmwareNot specified in the recordNot stated
SupermicroX13sae FirmwareNot specified in the recordNot stated
SupermicroX13sae-f FirmwareNot specified in the recordNot stated
SupermicroX13san-c FirmwareNot specified in the recordNot stated
SupermicroX13san-c-wohs FirmwareNot specified in the recordNot stated
SupermicroX13san-e FirmwareNot specified in the recordNot stated
SupermicroX13san-e-wohs FirmwareNot specified in the recordNot stated
SupermicroX13san-h FirmwareNot specified in the recordNot stated
SupermicroX13san-h-wohs FirmwareNot specified in the recordNot stated
SupermicroX13san-l FirmwareNot specified in the recordNot stated
SupermicroX13san-l-wohs FirmwareNot specified in the recordNot stated

Version data comes from the organisation that assigned the CVE; 35 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Official description

A shell-injection vulnerability in email notifications on Supermicro motherboards (such as H12DST-B before 03.10.35) allows remote attackers to inject execute arbitrary commands as root on the BMC.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Neutralization of Special Elements used in an OS Command

The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command before it is sent to a downstream component.

How developers prevent this class of flaw

  • If at all possible, use library calls rather than external processes to recreate the desired functionality.
  • For any data that will be used to generate a command to be executed, keep as much of that data out of external control as possible. For example, in web applications, this may require storing the data locally in the session's state instead of sending it out to the client in a hidden form field.
  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

More Improper Neutralization of Special Elements used in an OS Command vulnerabilities (CWE-78)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Technical write-ups (may include proof of concept)

Recent Improper Neutralization of Special Elements used in an OS Command vulnerabilities

Spotted an error? Tell us.