Process crash via stack buffer underflow
Published Dec 12, 2023 · Updated Nov 4, 2025
Stack buffer underflow in CountVowelPosition in eSpeak NG 1.52-dev allows local users to crash the process via a crafted input file. During phoneme synthesis, the function reads eight bytes from the stack redzone before the local plist array when it handles the crafted text. Execution requires a user or application to pass attacker-controlled text to local speech synthesis; the demonstrated result is process termination.
Summary
What happened
Stack buffer underflow in CountVowelPosition in eSpeak NG 1.52-dev allows local users to crash the process via a crafted input file. During phoneme synthesis, the function reads eight bytes from the stack redzone before the local plist array when it handles the crafted text. Execution requires a user or application to pass attacker-controlled text to local speech synthesis; the demonstrated result is process termination.
The record
- CVE
- CVE-2023-49991
- Published
- Dec 12, 2023
- Updated
- Nov 4, 2025
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-787, T1204.002, T1499
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Dec 12, 2023CVE publishedPublication date reported by the CVE source.
- Nov 4, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
- Issue 1825 proof-of-concept inputproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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