CVE-2022-24795

Published: 5 April 2022

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.

Notes

CVE is assigned to yajl-ruby. There is an unofficial patch for
yajl which will abort() too, though that is likely hardening and
isn't part of this CVE.

no upstream patch available as of 2023-06-07 for yajl. There is an
open pull request for the unofficial patch, however, the fix proposed
by the patch is being further discussed on the comments of this pull
request. The unofficial patch is being disputed by some, and new
patches have been proposed. More information at
https://github.com/lloyd/yajl/pull/240.

Status

Severity score breakdown

References

• https://github.com/brianmario/yajl-ruby/pull/211
• https://github.com/brianmario/yajl-ruby/security/advisories/GHSA-jj47-x69x-mxrm
• https://ubuntu.com/security/notices/USN-6233-1
• https://ubuntu.com/security/notices/USN-6233-2
• https://www.cve.org/CVERecord?id=CVE-2022-24795
• NVD
• Launchpad
• Debian

Bugs

• https://github.com/lloyd/yajl/issues/239