Description
In this scenario, libcurl first uses a proper HTTP/3 server for the initial transfers, and when it makes a second transfer to the same site it has been replaced by the attacker's impostor machine - without a valid certificate. When libcurl returns to the hostname the second time with a cached SSL session (`CURLOPT_SSL_SESSIONID_CACHE` is not disabled) and early data enabled (the `CURLSSLOPT_EARLYDATA` bit is set in `CURLOPT_SSL_OPTIONS`), libcurl might send off the second request's bytes on that new connection *before* enforcing the certificate verification failure. Potentially leaking sensitive information.
CVSS breakdown
CVSS 3.1
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Affected products
- curl / curl962097b8dd44ed5b9e7984bc1cdffdbdd566857f – 7b9613fa9b1a5e04301a3920eef58e8138dad05e
- curl / curl8.19.0 – 8.19.0
- curl / curl8.18.0 – 8.18.0
- curl / curl8.17.0 – 8.17.0
- curl / curl8.16.0 – 8.16.0
- curl / curl8.15.0 – 8.15.0
- curl / curl8.14.1 – 8.14.1
- curl / curl8.14.0 – 8.14.0
- curl / curl8.13.0 – 8.13.0
- curl / curl8.12.1 – 8.12.1
- curl / curl8.12.0 – 8.12.0
- curl / curl8.11.1 – 8.11.1
- curl / curl8.11.0 – 8.11.0
- curl / curl8.20.0 – 8.20.0
- curl / curl8.11.0 – 8.14.2
- curl / curl8.15.0 – 8.16.1
- curl / curl8.17.0 – 8.20.1
- haxx / curl8.11.0 – 8.21.0
Updated 44m ago · 8 sources