Summary
It was discovered that curl incorrectly reused non-TLS connections when
TLS was required in some STARTTLS configurations. A remote attacker could
possibly use this issue to obtain sensitive information. (CVE-2026-4873)
It was discovered that curl incorrectly reused certain HTTP Negotiate
connections. A remote attacker could possibly use this issue to obtain
sensitive information. (CVE-2026-5545)
It was discovered that curl incorrectly reused certain SMB connections. A
remote attacker could possibly use this issue to obtain sensitive
information. (CVE-2026-5773)
It was discovered that curl could leak proxy credentials when handling
redirects in some configurations. A remote attacker could possibly use
this issue to obtain sensitive information. (CVE-2026-6253)
It was discovered that curl could leak cookies because of stale custom
cookie host handling in some requests. A remote attacker could possibly
use this issue to obtain sensitive information. (CVE-2026-6276)
It was discovered that curl could leak .netrc credentials when reusing
proxy connections in some situations. A remote attacker could possibly use
this issue to obtain sensitive information. (CVE-2026-6429)
It was discovered that curl could leak Digest authentication state when
switching proxies in some situations. A remote attacker could possibly use
this issue to obtain sensitive information. (CVE-2026-7168)
Fixed packages 4
| Release | Package | Fixed in |
|---|---|---|
| Ubuntu · 22.04 LTS 22.04:LTS | curl | 7.81.0-1ubuntu1.24 |
| Ubuntu · 24.04 LTS 24.04:LTS | curl | 8.5.0-2ubuntu10.9 |
| Ubuntu · 25.10 | curl | 8.14.1-2ubuntu1.3 |
| Ubuntu · 26.04 LTS 26.04:LTS | curl | 8.18.0-1ubuntu2.1 |
References
-
report
https://ubuntu.com/security/CVE-2026-4873
-
report
https://ubuntu.com/security/CVE-2026-5545
-
report
https://ubuntu.com/security/CVE-2026-5773
-
report
https://ubuntu.com/security/CVE-2026-6253
-
report
https://ubuntu.com/security/CVE-2026-6276
-
report
https://ubuntu.com/security/CVE-2026-6429
-
report
https://ubuntu.com/security/CVE-2026-7168