Process memory corruption via wrapped string allocation
Published Apr 27, 2025 · Updated Apr 28, 2025
Heap-based buffer overflow in QuickJS before 2025-04-26 allows local users to corrupt process memory via a crafted serialized string. JS_ReadString accepts an oversized LEB128 length, and js_alloc_string_rt wraps the allocation-size calculation before header initialization writes beyond the undersized heap buffer. Exploitation requires an application to pass attacker-controlled serialized data to JS_ReadObject; the demonstrated result is memory corruption and a process crash.
Summary
What happened
Heap-based buffer overflow in QuickJS before 2025-04-26 allows local users to corrupt process memory via a crafted serialized string. JS_ReadString accepts an oversized LEB128 length, and js_alloc_string_rt wraps the allocation-size calculation before header initialization writes beyond the undersized heap buffer. Exploitation requires an application to pass attacker-controlled serialized data to JS_ReadObject; the demonstrated result is memory corruption and a process crash.
The record
- CVE
- CVE-2025-46687
- Published
- Apr 27, 2025
- Updated
- Apr 28, 2025
- Vendor
- Fabrice Bellard
- Product
- QuickJS
- Classifications
- CWE-770
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 27, 2025CVE publishedPublication date reported by the CVE source.
- Apr 28, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <2025-04-26
What conditions does exploitation require?
What is affected?
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
- Upstream issue 399 reproducerproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo