CVE-2021-22947 – curl: Server responses received before STARTTLS processed after TLS handshake
https://notcve.org/view.php?id=CVE-2021-22947
When curl >= 7.20.0 and <= 7.78.0 connects to an IMAP or POP3 server to retrieve data using STARTTLS to upgrade to TLS security, the server can respond and send back multiple responses at once that curl caches. curl would then upgrade to TLS but not flush the in-queue of cached responses but instead continue using and trustingthe responses it got *before* the TLS handshake as if they were authenticated.Using this flaw, it allows a Man-In-The-Middle attacker to first inject the fake responses, then pass-through the TLS traffic from the legitimate server and trick curl into sending data back to the user thinking the attacker's injected data comes from the TLS-protected server. Cuando en curl versiones posteriores a 7.20.0 incluyéndola, y versiones anteriores a 7.78.0 incluyéndola, se conecta a un servidor IMAP o POP3 para recuperar datos usando STARTTLS para actualizar a la seguridad TLS, el servidor puede responder y enviar múltiples respuestas a la vez que curl almacena en caché. curl entonces actualizaría a TLS pero no vaciaría la cola de respuestas almacenadas en caché, sino que continuaría usando y confiando en las respuestas que obtuvo *antes* del protocolo de enlace TLS como si estuvieran autenticadas. Usando este fallo, permite a un atacante de tipo Man-In-The-Middle inyectar primero las respuestas falsas, luego pasar mediante el tráfico TLS del servidor legítimo y engañar a curl para que envíe datos de vuelta al usuario pensando que los datos inyectados por el atacante provienen del servidor protegido por TLS A flaw was found in curl. The flaw lies in how curl handles cached or pipelined responses that it receives from either a IMAP, POP3, SMTP or FTP server before the TLS upgrade using STARTTLS. In such a scenario curl even after upgrading to TLS would trust these cached responses treating them as valid and authenticated and use them. • http://seclists.org/fulldisclosure/2022/Mar/29 https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf https://hackerone.com/reports/1334763 https://lists.debian.org/debian-lts-announce/2021/09/msg00022.html https://lists.debian.org/debian-lts-announce/2022/08/msg00017.html https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/APOAK4X73EJTAPTSVT7IRVDMUWVXNWGD https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RWLEC6YVEM2HWUBX67 • CWE-310: Cryptographic Issues CWE-319: Cleartext Transmission of Sensitive Information CWE-345: Insufficient Verification of Data Authenticity •
CVE-2021-22946 – curl: Requirement to use TLS not properly enforced for IMAP, POP3, and FTP protocols
https://notcve.org/view.php?id=CVE-2021-22946
A user can tell curl >= 7.20.0 and <= 7.78.0 to require a successful upgrade to TLS when speaking to an IMAP, POP3 or FTP server (`--ssl-reqd` on the command line or`CURLOPT_USE_SSL` set to `CURLUSESSL_CONTROL` or `CURLUSESSL_ALL` withlibcurl). This requirement could be bypassed if the server would return a properly crafted but perfectly legitimate response.This flaw would then make curl silently continue its operations **withoutTLS** contrary to the instructions and expectations, exposing possibly sensitive data in clear text over the network. Un usuario puede decirle a curl versiones posteriores a 7.20.0 incluyéndola , y versiones anteriores a 7.78.0 incluyéndola, que requiera una actualización con éxito a TLS cuando hable con un servidor IMAP, POP3 o FTP ("--ssl-reqd" en la línea de comandos o "CURLOPT_USE_SSL" configurado como "CURLUSESSL_CONTROL" o "CURLUSESSL_ALL" conlibcurl). Este requisito podría ser omitido si el servidor devolviera una respuesta correctamente diseñada pero perfectamente legítima. Este fallo haría que curl continuara silenciosamente sus operaciones **withoutTLS** en contra de las instrucciones y expectativas, exponiendo posiblemente datos confidenciales en texto sin cifrar a través de la red A flaw was found in curl. • http://seclists.org/fulldisclosure/2022/Mar/29 https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf https://hackerone.com/reports/1334111 https://lists.debian.org/debian-lts-announce/2021/09/msg00022.html https://lists.debian.org/debian-lts-announce/2022/08/msg00017.html https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/APOAK4X73EJTAPTSVT7IRVDMUWVXNWGD https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RWLEC6YVEM2HWUBX67 • CWE-319: Cleartext Transmission of Sensitive Information CWE-325: Missing Cryptographic Step •