CVE-2026-88359 Affecting libfyaml package, versions *
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published25 Sept 2026
- disclosed24 Sept 2026
Introduced: 24 Sep 2026
NewCVE-2026-88359 (opens in a new tab)How to fix?
There is no fixed version for Echo:latest libfyaml.
NVD Description
Note: Versions mentioned in the description apply only to the upstream libfyaml package and not the libfyaml package as distributed by Echo.
See How to fix? for Echo:latest relevant fixed versions and status.
libfyaml 0.9.6 contains a stack exhaustion vulnerability in fy_atom_iter_format(). When processing a specially crafted YAML document containing a very large literal or folded block scalar, the function repeatedly grows an internal buffer using alloca() inside a loop. The allocated stack memory is not released until the function returns, causing cumulative stack growth that can exceed the process stack limit and result in SIGSEGV and denial of service.