Vulnerability advisory

EEF-CVE-2026-48594

Decompression bomb in Tesla.Middleware.DecompressResponse and Tesla.Middleware.Compression

Published Jun 2, 2026Updated Sep 24, 2026OSV record ↗

Also known as CVE-2026-48594GHSA-mc85-72gr-vm9f

Severity

CVSS 4.0CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Affected versions

tesla Hex

All tesla advisories →

Affected Fixed in

0.6.0 to before 1.18.3 1.18.3Advisories →

Affected	Fixed in
`0.6.0` to before 1.18.3	`1.18.3`Advisories →
Also listed as affected (56) `0.10.0` `0.6.0` `0.7.0` `0.7.1` `0.7.2` `0.8.0` `0.9.0` `1.0.0` `1.0.0-beta.1` `1.1.0` `1.10.0` `1.10.1` `1.10.2` `1.10.3` `1.11.0` `1.11.1` `1.11.2` `1.12.0` `1.12.1` `1.12.2` `1.12.3` `1.13.0` `1.13.1` `1.13.2` `1.14.0` `1.14.1` `1.14.2` `1.14.3` `1.15.0` `1.15.1` `1.15.2` `1.15.3` `1.16.0` `1.17.0` `1.18.0` `1.18.1` `1.18.2` `1.2.0` `1.2.1` `1.3.0` `1.3.1` `1.3.2` `1.3.3` `1.4.0` `1.4.1` `1.4.2` `1.4.3` `1.4.4` `1.5.0` `1.5.1` `1.6.0` `1.6.1` `1.7.0` `1.8.0` `1.8.1` `1.9.0`

Also listed as affected (56)

Repository

Affected commits	Fixed by commit
GIT github.com/elixir-tesla/tesla ↗
5bd90bb5cf0d15e375edc2a66fa322292940fce2 to before 340f75b5d191dc747ef7ac6365bd002d1cd55a9d	`340f75b5d191dc747ef7ac6365bd002d1cd55a9d`

Description

Summary

Improper Handling of Highly Compressed Data (Data Amplification) vulnerability in elixir-tesla tesla allows a denial of service via decompression bomb in HTTP response bodies.

When Tesla.Middleware.DecompressResponse or Tesla.Middleware.Compression is included in a Tesla middleware pipeline, HTTP response bodies are decompressed eagerly with no size limit. The decompress_body/2 function in lib/tesla/middleware/compression.ex passes the entire response body to :zlib.gunzip/1 or :zlib.unzip/1 without any cap on the output size. Additionally, compression_algorithms/1 splits the content-encoding header on commas and decompress_body/2 recurses once per token, applying a decompression pass on each iteration. A server advertising content-encoding: gzip, gzip, gzip, gzip causes four recursive decompression passes, yielding exponential amplification: each gzip layer can expand its input roughly 1000x, so a payload of a few hundred bytes on the wire inflates to gigabytes of BEAM heap, exhausting memory and crashing or freezing the calling process.

This issue affects tesla: from 0.6.0 before 1.18.3.

Configurations

The application must include Tesla.Middleware.DecompressResponse or Tesla.Middleware.Compression in its Tesla middleware pipeline.