Unbounded recursion between Inspect.List charlist rendering and List.to_string/1 error path in Elixir
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.9epss 0.1%
exploitation probability
0.1%top 97% of all CVEs
observed exploitation
nono source reports it
Uncontrolled Recursion vulnerability in the Elixir standard library allows an attacker who controls a list passed to inspect/1, List.to_string/1, or List.to_charlist/1 to exhaust a BEAM node's memory.
Inspect.List's charlist branch in lib/elixir/lib/inspect.ex classifies a list as a charlist using List.ascii_printable?/2, which examines only the first :printable_limit (4096 by default) elements, and then calls IO.chardata_to_string/1 on the whole term. A list whose printable prefix exceeds that limit but which contains a later element that is not a code point (an atom, an out-of-range integer, or an improper tail) is therefore mis-classified, and the conversion raises ArgumentError. That conversion runs inside List.to_string/1, whose rescue clause builds its message by interpolating inspect(list), which re-enters the same branch and raises again. The nested inspection is an argument to raise, so the recursion is not in tail position and every level is retained: the process stack grows monotonically while each cycle re-walks the list, until the process is killed by max_heap_size or, by default, the node runs out of memory. List.to_charlist/1 has the same rescue shape.
Below the printable limit the inner inspect/1 sees the invalid element within its counter and renders the list in ordinary bracket form, so a single ArgumentError is raised and no recursion occurs.
This issue affects elixir: from 1.15.0-rc.0 before 1.18.5, from 1.19.0-rc.0 before 1.19.6, and from 1.20.0-rc.0 before 1.20.4.
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Affected products
elixir-lang · elixirReferences
https://cna.erlef.org/cves/CVE-2026-75758.htmlhttps://github.com/elixir-lang/elixir/commit/0bba5887577b1e328da825bd018815fdc519685ahttps://github.com/elixir-lang/elixir/commit/1eff1acffd49bdcc0d7f57ca74c1603328eed68ahttps://github.com/elixir-lang/elixir/commit/5230d73968f1b4969d2a2646786fa6c71475f5cchttps://github.com/elixir-lang/elixir/commit/a983c8c043b1fbf1d95df78a29149222dac2988chttps://github.com/elixir-lang/elixir/security/advisories/GHSA-jf5q-v438-665chttps://osv.dev/vulnerability/EEF-CVE-2026-75758