Application crash or code execution via parser double-free
Published Jan 22, 2020 · Updated Aug 5, 2024
Double free in libyang before 1.0-r1 allows context-dependent attackers to crash applications or execute code via a malformed YANG file. The yyerror routine frees param->value without clearing the pointer, so later parser cleanup frees the same allocation again after an unterminated organization field triggers an error. An affected application must parse an attacker-supplied YANG file; successful exploitation interrupts or executes code in that application's context.
Summary
What happened
Double free in libyang before 1.0-r1 allows context-dependent attackers to crash applications or execute code via a malformed YANG file. The yyerror routine frees param->value without clearing the pointer, so later parser cleanup frees the same allocation again after an unterminated organization field triggers an error. An affected application must parse an attacker-supplied YANG file; successful exploitation interrupts or executes code in that application's context.
The record
- CVE
- CVE-2019-20397
- Published
- Jan 22, 2020
- Updated
- Aug 5, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-415, T1203
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jan 22, 2020CVE publishedPublication date reported by the CVE source.
- Aug 5, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
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.
Public exploit references
- Malformed YANG crash reproducerproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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