CVE-2026-87863
HSTS response erases persisted entries
CVSS Score
0.0
EPSS Score
0.0%
EPSS Percentile
0th
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.
| Vendor | curl |
| Product | curl |
| Published | Oct 20, 2026 |
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Affected Versions
curl / curl
8.22.0 ≤ 8.22.0 8.21.0 ≤ 8.21.0 8.20.0 ≤ 8.20.0 8.19.0 ≤ 8.19.0 8.18.0 ≤ 8.18.0 8.17.0 ≤ 8.17.0 8.16.0 ≤ 8.16.0 8.15.0 ≤ 8.15.0 8.14.1 ≤ 8.14.1 8.14.0 ≤ 8.14.0 8.13.0 ≤ 8.13.0 8.12.1 ≤ 8.12.1 8.12.0 ≤ 8.12.0 8.11.1 ≤ 8.11.1 8.11.0 ≤ 8.11.0 8.10.1 ≤ 8.10.1 8.10.0 ≤ 8.10.0 8.9.1 ≤ 8.9.1 8.9.0 ≤ 8.9.0 8.8.0 ≤ 8.8.0 8.7.1 ≤ 8.7.1 8.7.0 ≤ 8.7.0 8.6.0 ≤ 8.6.0 8.5.0 ≤ 8.5.0 8.4.0 ≤ 8.4.0 8.3.0 ≤ 8.3.0 8.2.1 ≤ 8.2.1 8.2.0 ≤ 8.2.0
References
Credits
Stanislav Fort (Aisle Research) Daniel Stenberg