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Medium · 6.9 CVE-2026-65627 EEF-CVE-2026-65627EUVD-2026-110306GHSA-wfpv-qxp8-x5gm

Decompression bomb via unbounded zlib:inflate in jose_jwe_zip:uncompress/2

Published Oct 26, 2026 · Updated Nov 2, 2026 · Assigned by EEF

Description

Improper Handling of Highly Compressed Data (Data Amplification) vulnerability in potatosalad jose (erlang-jose) allows a remote attacker to exhaust a node's memory with a small crafted JWE token.

The jose_jwe_zip:uncompress/2 function in src/jwe/jose_jwe_zip.erl decompresses the DEFLATE-compressed plaintext of a JWE that carries the optional zip: DEF header by calling zlib:inflate/2 on the entire attacker-controlled stream, with no bound on the output size or the inflation ratio. Raw DEFLATE reaches ratios around 1000:1 on highly repetitive input, so a few-kilobyte token inflates to hundreds of megabytes or gigabytes in a single call.

Decompression runs automatically during decryption through jose_jwe:block_decrypt/2 (JOSE.JWE.block_decrypt/2 in Elixir), before the recipient can inspect or reject the payload. With the common asymmetric key-management algorithms (RSA-OAEP, ECDH-ES) an attacker needs only the recipient's public key to craft such a token, so no authentication or secret material is required. A single small token can exhaust the node's memory and crash the BEAM, denying service to all users.

This issue affects jose: from 1.0.0 before 1.11.13.

Affected products

VendorProductAffectedFixed
potatosalad jose 1.0.0 – < 1.11.13 1.11.13

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

ReleasePackageFixed inAdvisory
Debian 14 erlang-jose 1.11.13-1 —
Debian 13 erlang-jose No fix yet —
Debian 12 erlang-jose No fix yet —
ReleasePackageFixed inAdvisory
Ubuntu 26.10 jose No fix yet —
Ubuntu 26.04 LTS jose No fix yet —
Ubuntu 24.04 LTS jose No fix yet —
Ubuntu 22.04 LTS jose No fix yet —
Ubuntu 20.04 LTS jose No fix yet —
Show 1 more (older releases, extended support, other products)
ReleasePackageFixed inAdvisory
Ubuntu 18.04 LTS jose No fix yet —

Azure Linux

ReleasePackageFixed inAdvisory
Azure Linux 3 jose +1 No fix yet —

Affected packages

EcosystemPackageAffectedFixedRecord
Hex jose >= 1.0.0, < 1.11.13 1.11.13 EEF-CVE-2026-65627

References