Host application crash via regexp source use-after-free
Published Jul 7, 2023 · Updated Nov 12, 2024
Use-after-free in MuJS before 1.1.2 allows attackers to crash a host application by accessing a regular expression's source property. The jsR_hasproperty path passes the garbage-collectable source buffer to js_pushliteral, which retains the pointer instead of copying the string. A host must execute attacker-controlled JavaScript and collect the original regexp before consuming the retained value; the bounded consequence is a host-process crash.
Summary
What happened
Use-after-free in MuJS before 1.1.2 allows attackers to crash a host application by accessing a regular expression's source property. The jsR_hasproperty path passes the garbage-collectable source buffer to js_pushliteral, which retains the pointer instead of copying the string. A host must execute attacker-controlled JavaScript and collect the original regexp before consuming the retained value; the bounded consequence is a host-process crash.
The record
- CVE
- CVE-2021-33796
- Published
- Jul 7, 2023
- Updated
- Nov 12, 2024
- Vendor
- Artifex Software, Inc.
- Product
- MuJS
- Classifications
- CWE-416, CAPEC-131, T1499
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 7, 2023CVE publishedPublication date reported by the CVE source.
- Nov 12, 2024Record updatedLatest update available in the CVE record.
Exploitability
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Is a vulnerable build present?
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- Affected versionversion=1.1.1 <=all
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What is affected?
Published CVSS scores
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Attacks
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