CyberSecBulletin
CVE-2023-28754NVD status: Modified

ShardingSphere-Agent: Deserialization of Untrusted Data

Published Updated By the CyberSecBulletin desk

CVE-2023-28754 is a high-severity deserialization of untrusted data vulnerability in ShardingSphere-Agent from Apache, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected ShardingSphere-Agent versions: 5.3.2 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 1.46% chance of exploitation within 30 days, higher than 74% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of ShardingSphere-Agent you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
ApacheShardingSphere-Agent5.3.2 and earlierNot stated
Apacheshardingsphere5.3.2 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
LowA basic user account is enough.
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:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.8HighNVD
CVSS 3.18.8HighCISA (ADP)

Official description

Deserialization of Untrusted Data vulnerability in Apache ShardingSphere-Agent, which allows attackers to execute arbitrary code by constructing a special YAML configuration file. The attacker needs to have permission to modify the ShardingSphere Agent YAML configuration file on the target machine, and the target machine can access the URL with the arbitrary code JAR. An attacker can use SnakeYAML to deserialize java.net.URLClassLoader and make it load a JAR from a specified URL, and then deserialize javax.script.ScriptEngineManager to load code using that ClassLoader. When the ShardingSphere JVM process starts and uses the ShardingSphere-Agent, the arbitrary code specified by the attacker will be executed during the deserialization of the YAML configuration file by the Agent. This issue affects ShardingSphere-Agent: through 5.3.2. This vulnerability is fixed in Apache ShardingSphere 5.4.0.

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

The underlying weakness: Deserialization of Untrusted Data

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

How developers prevent this class of flaw

  • If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
  • When deserializing data, populate a new object rather than just deserializing. The result is that the data flows through safe input validation and that the functions are safe.
  • Explicitly define a final object() to prevent deserialization.

More Deserialization of Untrusted Data vulnerabilities (CWE-502)

Timeline

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

References

Recent Deserialization of Untrusted Data vulnerabilities

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