Parser crash via underallocated pattern array
Published Jan 22, 2020 · Updated Aug 5, 2024
Memory corruption in CESNET libyang before 1.0-r1 allows attackers to crash a parsing process with a malformed YANG pattern statement. The yyparse pattern_stmt handler allocates only the first slot of a patterns_pcre pair, then passes an unallocated companion slot to yang_read_pattern during lys_parse_path parsing. A target application must parse attacker-supplied YANG content; the demonstrated consequence is a segmentation fault and service interruption, not code execution.
Summary
What happened
Memory corruption in CESNET libyang before 1.0-r1 allows attackers to crash a parsing process with a malformed YANG pattern statement. The yyparse pattern_stmt handler allocates only the first slot of a patterns_pcre pair, then passes an unallocated companion slot to yang_read_pattern during lys_parse_path parsing. A target application must parse attacker-supplied YANG content; the demonstrated consequence is a segmentation fault and service interruption, not code execution.
The record
- CVE
- CVE-2019-20396
- Published
- Jan 22, 2020
- Updated
- Aug 5, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-119, T1499.004
- 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 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.
Weakness, pattern, technique
Public exploit references
- Malformed YANG pattern proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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