Object prototype modification via unchecked __proto__ copy
Published Sep 17, 2021 · Updated Aug 4, 2024
Prototype pollution in Baidu ZRender 4.3.2 and earlier and 5.0.0 through 5.2.0 allows attackers to alter inherited object properties. The merge, clone, and extend loops in src/core/util.ts copy an own proto key into destination objects instead of rejecting it. Reachability depends on a consuming application passing attacker-controlled object keys into these helpers; the resulting prototype changes can disrupt that application's behavior.
Summary
What happened
Prototype pollution in Baidu ZRender 4.3.2 and earlier and 5.0.0 through 5.2.0 allows attackers to alter inherited object properties. The merge, clone, and extend loops in src/core/util.ts copy an own proto key into destination objects instead of rejecting it. Reachability depends on a consuming application passing attacker-controlled object keys into these helpers; the resulting prototype changes can disrupt that application's behavior.
The record
- CVE
- CVE-2021-39227
- Published
- Sep 17, 2021
- Updated
- Aug 4, 2024
- Vendor
- Baidu
- Product
- ZRender
- Classifications
- CWE-915, CWE-1321
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 17, 2021CVE publishedPublication date reported by the CVE source.
- Aug 4, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 5.2.1
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- ZRender merge prototype-pollution proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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