Reference page — cumulative record through Sunday, October 4, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
AV AC PR UI S C I A CVSS EPSS %ile KEV N H N N U L H N 6.5 .0051 41.4 —
AFFECTED Product Versions Fixed curl 7.10.6 – — curl e56ae1426cb7a0a4a427cf8d6099a821fdaae428 – — curl 8.19.0 – —
TIMELINE Apr 4 Reserved by curl May 13 Published (CNA: curl) Sep 15 EXPLOIT PUBLISHED — CVE-2026-5545 (curl). Public exploit reference added.
libcurl might in some circumstances reuse the wrong connection when asked to do an authenticated HTTP(S) request after a Negotiate-authenticated one, when both use the same host. libcurl features a pool of recent connections so that subsequent requests can reuse an existing connection to avoid overhead. When reusing a connection a range of criteria must be met. Due to a logical error in the code, a request that was issued by an application could wrongfully reuse an existing connection to the same server that was authenticated using different credentials. An application that first uses Negotiate authentication to a server with `user1:password1` and then does another operation to the same server asking for any authentication method but for `user2:password2` (while the previous connection is still alive) - the second request gets confused and wrongly reuses the same connection and sends the new request over that connection thinking it uses a mix of user1's and user2's credentials when it is in fact still using the connection authenticated for user1...
| Date | Event | Detail |
|---|---|---|
| April 4, 2026 | Reserved | Reserved by curl |
| May 13, 2026 | Published | Published (CNA: curl) |
| September 15, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-5545 (curl). Public exploit reference added. |
Authoritative record: CVE-2026-5545 at cve.org
Vendors: curl
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-5545 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Sunday, October 4, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.
