This page tracks the Ubuntu fix status. The vulnerability itself is described on the main CVE page. View CVE-2026-88359 →

UBUNTU-CVE-2026-88359

libfyaml 0.9.6 contains a stack exhaustion vulnerability in fy_atom_iter_format(). When processing a specially crafted YAML document containing a very...

Original description

The description as published by the source.

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.

Source: OSV.dev (Open Source Vulnerabilities) OSV

Affected packages

Ubuntu:22.04:LTS libfyaml

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

Ubuntu:24.04:LTS libfyaml

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

Ubuntu:26.10 libfyaml

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

Ubuntu:26.04:LTS libfyaml

[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}]

References

report ubuntu.com
report cve.org