Vulnerabilities > CVE-2022-24795 - Heap-based Buffer Overflow vulnerability in Yajl-Ruby Project Yajl-Ruby
Summary
yajl-ruby is a C binding to the YAJL JSON parsing and generation library. The 1.x branch and the 2.x branch of `yajl` contain an integer overflow which leads to subsequent heap memory corruption when dealing with large (~2GB) inputs. The reallocation logic at `yajl_buf.c#L64` may result in the `need` 32bit integer wrapping to 0 when `need` approaches a value of 0x80000000 (i.e. ~2GB of data), which results in a reallocation of buf->alloc into a small heap chunk. These integers are declared as `size_t` in the 2.x branch of `yajl`, which practically prevents the issue from triggering on 64bit platforms, however this does not preclude this issue triggering on 32bit builds on which `size_t` is a 32bit integer. Subsequent population of this under-allocated heap chunk is based on the original buffer size, leading to heap memory corruption. This vulnerability mostly impacts process availability. Maintainers believe exploitation for arbitrary code execution is unlikely. A patch is available and anticipated to be part of yajl-ruby version 1.4.2. As a workaround, avoid passing large inputs to YAJL.
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Forced Integer Overflow This attack forces an integer variable to go out of range. The integer variable is often used as an offset such as size of memory allocation or similarly. The attacker would typically control the value of such variable and try to get it out of range. For instance the integer in question is incremented past the maximum possible value, it may wrap to become a very small, or negative number, therefore providing a very incorrect value which can lead to unexpected behavior. At worst the attacker can execute arbitrary code.
References
- https://github.com/brianmario/yajl-ruby/security/advisories/GHSA-jj47-x69x-mxrm
- https://github.com/brianmario/yajl-ruby/blob/7168bd79b888900aa94523301126f968a93eb3a6/ext/yajl/yajl_buf.c#L64
- https://github.com/brianmario/yajl-ruby/commit/7168bd79b888900aa94523301126f968a93eb3a6
- https://lists.debian.org/debian-lts-announce/2023/07/msg00013.html
- https://lists.debian.org/debian-lts-announce/2023/08/msg00003.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KLE3C4CECEJ4EUYI56KXI6OWACWXX7WN/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YO32YDJ74DADC7CMJNLSLBVWN5EXGF5J/