Skip to content

GHSA-qv4q-mr5r-qprj CVE-2022-23476

Unchecked return value from xmlTextReaderExpand

High RubyGems
Severity
7.5 / 10
High · CVSS 3.1
Exploit chance (EPSS)
1.82%
Chance of exploitation in the next 30 days. Higher than 78.79% of scored vulnerabilities.
Known exploited
No
Not in CISA's catalog
Weakness
CWE-252 Unchecked Return Value
CWE-476 NULL Pointer Dereference
Fix
1.13.10
Upgrade nokogiri to this version or later

Description

Summary

Nokogiri 1.13.8, 1.13.9 fails to check the return value from xmlTextReaderExpand in the method Nokogiri::XML::Reader#attribute_hash. This can lead to a null pointer exception when invalid markup is being parsed.

For applications using XML::Reader to parse untrusted inputs, this may potentially be a vector for a denial of service attack.

Mitigation

Upgrade to Nokogiri >= 1.13.10.

Users may be able to search their code for calls to either XML::Reader#attributes or XML::Reader#attribute_hash to determine if they are affected.

Severity

The Nokogiri maintainers have evaluated this as High Severity 7.5 (CVSS3.1).

References

Credit

This vulnerability was responsibly reported by @davidwilemski.

Affected versions

RubyGems

PackageVulnerableFixed in
nokogiri
>= 1.13.8, < 1.13.10
1.13.10

How to fix

Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.

nokogiri RubyGems → 1.13.10

bundler
bundle update nokogiri # Gemfile: gem "nokogiri", ">= 1.13.10"

Severity breakdown

CVSS 3.1 7.5

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Weakness

CWE-252: Unchecked Return Value

The product does not check the return value from a method or function, which can prevent it from detecting unexpected states and conditions.

How to prevent it
  • Implementation: Check the results of all functions that return a value and verify that the value is expected.
  • Implementation: For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished [REF-1484].
  • Implementation: Ensure that you account for all possible return values from the function.
  • Implementation: When designing a function, make sure you return a value or throw an exception in case of an error.

CWE-476: NULL Pointer Dereference

The product dereferences a pointer that it expects to be valid but is NULL.

How to prevent it
  • Implementation: For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished [REF-1484].
  • Requirements: Select a programming language that is not susceptible to these issues.
  • Implementation: Check the results of all functions that return a value and verify that the value is non-null before acting upon it.
  • Architecture and Design: Identify all variables and data stores that receive information from external sources, and apply input validation to make sure that they are only initialized to expected values.
  • Implementation: Explicitly initialize all variables and other data stores, either during declaration or just before the first usage.

References

Timeline

  1. Published
  2. Last updated by the source
  3. Latest EPSS score
AdvisorySeverityWhy it's related
GHSA-phwj-rprq-35pp
Nokogiri: Possible Use-After-Free when setting an attribute value via `Nokogiri::XML::Attr#value=` or `#content=`
High Also affects nokogiri
GHSA-wfpw-mmfh-qq69
Nokogiri: Possible Use-After-Free in XInclude Processing
Low Also affects nokogiri
GHSA-p67v-3w7g-wjg7
Nokogiri: Possible Use-After-Free when directly using `NokogirI::XML::XPathContext` beyond document lifetime
Medium Also affects nokogiri
GHSA-wjv4-x9w8-wm3h
Nokogiri: Possible Use-After-Free when setting `Document#root=` to an invalid node type
Medium Also affects nokogiri
GHSA-5prr-v3j2-97mh
Nokogiri: Possible Out-of-Bounds Read in `Nokogiri::XML::NodeSet#[]`
High Also affects nokogiri
GHSA-9cv2-cfxc-v4v2
Nokogiri: Null Pointer Dereference calling methods on uninitialized wrapper classes
High Also affects nokogiri
GHSA-8678-w3jw-xfc2
Nokogiri: XML::Schema on JRuby allows network requests when NONET is set, bypassing CVE-2020-26247
Low Also affects nokogiri
GHSA-5v8h-3h3q-446p
Nokogiri: Possible Use-After-Free when `Nokogiri::XML::Document#encoding=` raises an exception
High Also affects nokogiri
Is this in your code?

MergeHarbor checks every repository's dependencies against this database, ranks what matters by exploitability and reachability, routes it to the owning team and opens the fix pull request.

Check your repos with MergeHarbor