Cyber Resilience

CVE-2026-9547

Haxx Curl 7.69.0 – 8.21.0

Public PoC
Published
03 July 2026
Modified
07 July 2026
Patch / advisory
CVSS Score v3.1 7.4
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS Score 0.0032 25th percentile
Risk Priority 56 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-9547 is a high-severity an unspecified weakness vulnerability in Haxx Curl. Its CVSS base score is 7.4 (High).

Operationally, ranked at the 25th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability Data

When a libcurl-based application performs transfers via `SCP://` or `SFTP://` and utilizes the `CURLOPT_SSH_KEYFUNCTION` callback, it may silently accept an untrusted server. This vulnerability occurs when a server presents a host key type that does not match the specific key…

more

type already recorded for that host in the `known_hosts` file. Instead of rejecting the mismatch, the callback mechanism fails to properly enforce the restriction, allowing the connection to succeed without warning and risking a potential man-in-the-middle attack.

CWE(s)

Related Threats

CVEs Like This One

CVE-2026-8458Same product: Haxx Curl
CVE-2026-5773Same product: Haxx Curl
CVE-2025-15079Same product: Haxx Curl
CVE-2024-0853Same product: Haxx Curl
CVE-2026-3784Same product: Haxx Curl
CVE-2026-3805Same product: Haxx Curl
CVE-2026-10536Same product: Haxx Curl
CVE-2025-14819Same product: Haxx Curl
CVE-2026-11586Same product: Haxx Curl
CVE-2025-15224Same product: Haxx Curl

Affected Assets

haxx
curl
7.69.0 — 8.21.0

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References