Dashboard / CVE-2026-86409

CVE-2026-86409

HIGH
MEDIUM Priority: 0.03 BB Relevance: 66/100
Published: 2026-10-20 Modified: 2026-10-29 First seen: 2026-10-29 Status: active

Attack Surface

Network No Auth No Interaction Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Network
AC: High
PR: None
UI: None
S: Unchanged
C: High
I: High
A: High

Description

Setting `CURLOPT_AWS_SIGV4` to NULL but does not disable SigV4 authentication, contrary to expectations and documentation. A subsequent transfer on the same handle still sends an `Authorization: AWS4-HMAC-SHA256` header to whatever URL isset next, leaking state information.

Weakness Classification (1)

Affected Software (1)

VendorProductVersion
curl curl 8.21.0

References & Advisories (3)

Bug Bounty Relevance

66 / 100
✓ Network accessible
✓ No authentication
✓ No user interaction

CVSS Score

8.1 / 10.0 v3.1
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploitation Probability

0.31%
Raw Score 0.003130
Percentile 24.2%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00313
2026-10-28
0.00313

Intelligence Sources

mitre ref →
nvd ref →

External Links