CVE-2026-65627

MEDIUM
MEDIUM Priority: 0.02 BB Relevance: 49/100
Published: 2026-10-26 Modified: 2026-10-27 First seen: 2026-10-29 Status: active

Attack Surface

Low Complexity No Auth No Interaction

CVSS Vector Breakdown

AV: Local
AC: Low
PR: None
UI: None
S: X
AT: None
VC: None
VI: None
VA: High

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.

Weakness Classification (1)

Bug Bounty Relevance

49 / 100
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

6.9 / 10.0 v4.0
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

EPSS — Exploitation Probability

0.25%
Raw Score 0.002490
Percentile 16.2%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00249
2026-10-28
0.00249

Intelligence Sources

mitre ref →
nvd ref →