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CVE-2023-0776NVD status: Modified

Nova 436Q: Improper Neutralization of Special Elements used in a Command

CVE-2023-0776 is a critical-severity improper neutralization of special elements used in a command vulnerability in Nova 436Q from Baicells, with a CVSS 3.1 base score of 10.0 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Nova 436Q versions: 2.12.7 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.19% chance of exploitation within 30 days, higher than 69% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of Nova 436Q you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on baicells.com for workarounds and exact fixed builds.
  3. 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
BaicellsNova 436Q2.12.7 and earlierNot stated
BaicellsNova 430E2.12.7 and earlierNot stated
BaicellsNova 430I2.12.7 and earlierNot stated
BaicellsNeutrino 4302.12.7 and earlierNot stated
BaicellsNeutrino 430 Firmwareqrtb_2.12.7 and earlierNot stated
BaicellsNova430l Firmwareqrtb_2.12.7 and earlierNot stated
BaicellsNova430e Firmwareqrtb_2.12.7 and earlierNot stated
BaicellsNova436q Firmwareqrtb_2.12.7 and earlierNot stated

Version data comes from the organisation that assigned the CVE. 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
ChangedThe attack can reach beyond the vulnerable component into other systems.
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:C/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.1HighCNA (baicells.com)
CVSS 3.110.0CriticalNVD

Official description

Baicells Nova 436Q, Nova 430E, Nova 430I, and Neutrino 430 LTE TDD eNodeB devices with firmware through QRTB 2.12.7 are vulnerable to remote shell code exploitation via HTTP command injections. Commands are executed using pre-login execution and executed with root permissions. The following methods below have been tested and validated by a 3rd party analyst and has been confirmed exploitable special thanks to Rustam Amin for providing the steps to reproduce.

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 a Command

The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when 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.
  • If possible, ensure that all external commands called from the program are statically created.
  • Run time: Run time policy enforcement may be used in an allowlist fashion to prevent use of any non-sanctioned commands.

More Improper Neutralization of Special Elements used in a Command vulnerabilities (CWE-77)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Improper Neutralization of Special Elements used in a Command vulnerabilities

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