Curl 8.2.0 < 8.23.0 HSTS Cache Erasure

medium Nessus Plugin ID 371145

Synopsis

The remote host has a program that is affected by a data loss vulnerability.

Description

The version of curl installed on the remote host is 8.2.0 prior to 8.23.0. It is, therefore, affected by a data loss vulnerability:

- An authenticated HTTPS origin can supply an HSTS max-age value that the parser accepts, but time serialization later fails to process. On 64-bit systems, extreme max-age values compute an absolute expiry within standard time integer limits that exceeds calendar time structure bounds. During cache saves, the original HSTS file is truncated before writing a temporary replacement; when serialization fails, the temporary file is deleted, leaving an empty or partial cache. Because the save error is silently ignored during cleanup, curl exits successfully despite the data loss. (CVE-2026-87863)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Upgrade Curl to version 8.23.0 or later.

Plugin Details

Severity: Medium

ID: 371145

File Name: curl_CVE-2026-87863.nasl

Version: 1.1

Type: Local

Agent: windows, macosx, unix

Family: Misc.

Published: 10/23/2026

Updated: 10/23/2026

Configuration: Enable thorough checks (optional)

Supported Sensors: Nessus Agent, Continuous Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

CVSS Score Rationale: Score from an analysis done by tenable

VPR

Risk Factor: Medium

Score: 4.9

Percentile: 58.48

CVSS v3

Risk Factor: Medium

Base Score: 5.3

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Vulnerability Information

CPE: cpe:/a:haxx:curl

Required KB Items: installed_sw/Curl

Patch Publication Date: 10/14/2026

Vulnerability Publication Date: 10/14/2026

Reference Information

CVE: CVE-2026-87863

IAVA: 2026-A-1143

Detections

Analytics