CVE-2026-87863
Received
Received - Intake
HSTS max-age Overflow Leading to Cache Corruption in curl
Vulnerability report for CVE-2026-87863, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-20
Last updated on: 2026-10-20
Assigner: curl
Description
Description
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.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| curl | curl | 8.22.0 |
| curl | curl | 8.21.0 |
| curl | curl | 8.20.0 |
| curl | curl | 8.19.0 |
| curl | curl | 8.18.0 |
| curl | curl | 8.17.0 |
| curl | curl | 8.16.0 |
| curl | curl | 8.15.0 |
| curl | curl | 8.14.1 |
| curl | curl | 8.14.0 |
| curl | curl | 8.13.0 |
| curl | curl | 8.12.1 |
| curl | curl | 8.12.0 |
| curl | curl | 8.11.1 |
| curl | curl | 8.11.0 |
| curl | curl | 8.10.1 |
| curl | curl | 8.10.0 |
| curl | curl | 8.9.1 |
| curl | curl | 8.9.0 |
| curl | curl | 8.8.0 |
| curl | curl | 8.7.1 |
| curl | curl | 8.7.0 |
| curl | curl | 8.6.0 |
| curl | curl | 8.5.0 |
| curl | curl | 8.4.0 |
| curl | curl | 8.3.0 |
| curl | curl | 8.2.1 |
| curl | curl | 8.2.0 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
