High severity · published Feb 27, 2026
CVE-2026-21619
Unsafe Deserialization of Erlang Terms in hex_core
7.5
CVSS
0.6%
EPSS
No
On KEV
Description
Uncontrolled Resource Consumption, Deserialization of Untrusted Data vulnerability in hexpm hex_core (hex_api modules), hexpm hex (mix_hex_api modules), erlang rebar3 (r3_hex_api modules) allows Object Injection, Excessive Allocation. This vulnerability is associated with program files src/hex_api.erl, src/mix_hex_api.erl, apps/rebar/src/vendored/r3_hex_api.erl and program routines hex_core:request/4, mix_hex_api:request/4, r3_hex_api:request/4.
This issue affects hex_core: from 0.1.0 before 0.12.1; hex: from 2.3.0 before 2.3.2; rebar3: from 3.9.1 before 3.27.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 50% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HE
hex · hexpm
314546ac432229518714cc8e3336e916b9da6305 before 636739f3322514e9303ca335fb630696fcbb3c95; 2.3.0 before 2.3.2 · source: vendor, NVD
HE
hex_core · hexpm
eb327f8edfe45507351e38cc0805aa12fa647f0b before cdf726095bca85ad2549d146df1e831ae93c2b13; 0.1.0 before 0.12.1 · source: vendor
RE
rebar3 · erlang
209c02ec57c2cc3207ee0174c3af3675b8dc8f79 before 1d4478f527e373de0b225951e53115450e0d9b9d; 3.9.1 before 3.27.0 · source: vendor, NVD
HC
Hex Core · Hex
0.1.0 before 0.12.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-21619
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-21619
cna.erlef.org
https://cna.erlef.org/cves/CVE-2026-21619.html
Patch
https://github.com/erlang/rebar3/commit/1d4478f527e373de0b225951e53115450e0d9b9d
Patch
https://github.com/hexpm/hex/commit/636739f3322514e9303ca335fb630696fcbb3c95
Patch
https://github.com/hexpm/hex_core/commit/cdf726095bca85ad2549d146df1e831ae93c2b13
Mitigation
https://github.com/hexpm/hex_core/security/advisories/GHSA-hx9w-f2w9-9g96
osv.dev
https://osv.dev/vulnerability/EEF-CVE-2026-21619
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