CVE-2026-86409
priority · track · 0EPSS 0.002 · 15 %ileDEFRUSEPSS · scored 2026-10-22
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.
cvss
Technical severity, 0–10. One row per scoring source.
No CVSS score recorded.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (4)
Products and version ranges known to be affected.
advisories (4)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-3904cURL: Mehrere SchwachstellenDeutsch2026-10-13csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in cURL ausnutzen, um beliebigen Programmcode auszuführen, Sicherheitsmaßnahmen zu umgehen, vertrauliche Informationen offenzulegen, Daten zu manipulieren oder einen Denial-of-Service-Zustand auszulösen.
- CERTFR-2026-AVI-1307Multiples vulnérabilités dans CurlFrançais2026-10-14vendor · certfrFR
- CERTFR-2026-AVI-1376Multiples vulnérabilités dans le noyau Linux d'UbuntuFrançais2026-10-23vendor · certfrFR
- CURL-CVE-2026-86409stale SigV4 headers sent unintended2026-10-14vendor · osvUS
Setting `CURLOPT_AWS_SIGV4` to NULL 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 is set next, leaking state information.
sources
Which sources assert this record, and when.
references (3) nvd
External citations — patches, advisories, analysis.
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