CyberSecBulletin
CVE-2021-20028Exploited in the wildNVD status: Analyzed

SonicWall Secure Remote Access (SRA) SQL Injection

Published Updated By the CyberSecBulletin desk

CVE-2021-20028 is a critical-severity improper neutralization of special elements used in an SQL command vulnerability in SonicWall SRA/SMA100 from SonicWall, 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. Affected SonicWall SRA/SMA100 versions: 8.x firmware; 9.0.0.9-26sv and earlier.. The record does not name a fixed version, so check the vendor advisory. CISA added it to the Known Exploited Vulnerabilities catalogue on March 28, 2022, which means attacks have been observed in the wild, including in ransomware campaigns.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Update Sma 210 Firmware to 9.0.0.10-28sv or a later version.
  2. Update Sma 410 Firmware to 9.0.0.10-28sv or a later version.
  3. Update Sma 500v Firmware to 9.0.0.10-28sv or a later version.
  4. CISA's required action: The impacted product is end-of-life and should be disconnected if still in use.
  5. Read the advisory on psirt.global.sonicwall.com for workarounds and exact fixed builds.
  6. 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
SonicWallSonicWall SRA/SMA1008.x firmware; 9.0.0.9-26sv and earlier.Not stated
SonicWallSma 210 Firmware8.0.0.0 up to, but not including, 9.0.0.10-28sv9.0.0.10-28sv
SonicWallSma 410 Firmware8.0.0.0 up to, but not including, 9.0.0.10-28sv9.0.0.10-28sv
SonicWallSma 500v Firmware8.0.0.0 up to, but not including, 9.0.0.10-28sv9.0.0.10-28sv
SonicWallSra 4600 Firmware8.0.0.0 up to, but not including, 9.0.0.10-28sv9.0.0.10-28sv
SonicWallSra 1600 Firmware8.0.0.0 up to, but not including, 9.0.0.10-28sv9.0.0.10-28sv
SonicWallSra Va Firmware8.0.0.0 up to, but not including, 9.0.0.10-28sv9.0.0.10-28sv

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
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.

Scoring systemScoreSeverityScored by
CVSS 3.19.8CriticalNVD
CVSS 3.19.8CriticalCISA (ADP)
CVSS 2.07.5HighNVD

Official description

Improper neutralization of a SQL Command leading to SQL Injection vulnerability impacting end-of-life Secure Remote Access (SRA) products, specifically the SRA appliances running all 8.x firmware and 9.0.0.9-26sv or earlier

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 SQL Command

The product constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component. Without sufficient removal or quoting of SQL syntax in user-controllable inputs, the generated SQL query can cause those inputs to be interpreted as SQL instead of ordinary user data.

How developers prevent this class of flaw

  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using persistence layers such as Hibernate or Enterprise Java Beans, which can provide significant protection against SQL injection if used properly.
  • 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.
  • When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.

More Improper Neutralization of Special Elements used in an SQL Command vulnerabilities (CWE-89)

Timeline

  1. CVE record published.
  2. Added to CISA's Known Exploited Vulnerabilities catalogue.
  3. Deadline for US federal agencies to remediate, set by CISA.
  4. CISA published its SSVC assessment (exploitation: active, automatable: yes, technical impact: total).
  5. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in SonicWall SRA/SMA100

All SonicWall SRA/SMA100 vulnerabilities

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

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