CVE-2024-5535

Issue summary: Calling the OpenSSL API function SSL_select_next_proto with an empty supported client protocols buffer may cause a crash or memory contents to be sent to the peer. Impact summary: A buffer overread can have a range of potential consequences such as unexpected application beahviour or a crash. In particular this issue could result in up to 255 bytes of arbitrary private data from memory being sent to the peer leading to a loss of confidentiality. However, only applications that directly call the SSL_select_next_proto function with a 0 length list of supported client protocols are affected by this issue. This would normally never be a valid scenario and is typically not under attacker control but may occur by accident in the case of a configuration or programming error in the calling application. The OpenSSL API function SSL_select_next_proto is typically used by TLS applications that support ALPN (Application Layer Protocol Negotiation) or NPN (Next Protocol Negotiation). NPN is older, was never standardised and is deprecated in favour of ALPN. We believe that ALPN is significantly more widely deployed than NPN. The SSL_select_next_proto function accepts a list of protocols from the server and a list of protocols from the client and returns the first protocol that appears in the server list that also appears in the client list. In the case of no overlap between the two lists it returns the first item in the client list. In either case it will signal whether an overlap between the two lists was found. In the case where SSL_select_next_proto is called with a zero length client list it fails to notice this condition and returns the memory immediately following the client list pointer (and reports that there was no overlap in the lists). This function is typically called from a server side application callback for ALPN or a client side application callback for NPN. In the case of ALPN the list of protocols supplied by the client is guaranteed by libssl to never be zero in length. The list of server protocols comes from the application and should never normally be expected to be of zero length. In this case if the SSL_select_next_proto function has been called as expected (with the list supplied by the client passed in the client/client_len parameters), then the application will not be vulnerable to this issue. If the application has accidentally been configured with a zero length server list, and has accidentally passed that zero length server list in the client/client_len parameters, and has additionally failed to correctly handle a "no overlap" response (which would normally result in a handshake failure in ALPN) then it will be vulnerable to this problem. In the case of NPN, the protocol permits the client to opportunistically select a protocol when there is no overlap. OpenSSL returns the first client protocol in the no overlap case in support of this. The list of client protocols comes from the application and should never normally be expected to be of zero length. However if the SSL_select_next_proto function is accidentally called with a client_len of 0 then an invalid memory pointer will be returned instead. If the application uses this output as the opportunistic protocol then the loss of confidentiality will occur. This issue has been assessed as Low severity because applications are most likely to be vulnerable if they are using NPN instead of ALPN - but NPN is not widely used. It also requires an application configuration or programming error. Finally, this issue would not typically be under attacker control making active exploitation unlikely. The FIPS modules in 3.3, 3.2, 3.1 and 3.0 are not affected by this issue. Due to the low severity of this issue we are not issuing new releases of OpenSSL at this time. The fix will be included in the next releases when they become available.
References
Link Resource
http://www.openwall.com/lists/oss-security/2024/06/27/1
http://www.openwall.com/lists/oss-security/2024/06/28/4
https://github.com/openssl/openssl/commit/4ada436a1946cbb24db5ab4ca082b69c1bc10f37
https://github.com/openssl/openssl/commit/99fb785a5f85315b95288921a321a935ea29a51e
https://github.com/openssl/openssl/commit/cf6f91f6121f4db167405db2f0de410a456f260c
https://github.com/openssl/openssl/commit/e86ac436f0bd54d4517745483e2315650fae7b2c
https://github.openssl.org/openssl/extended-releases/commit/9947251413065a05189a63c9b7a6c1d4e224c21c
https://github.openssl.org/openssl/extended-releases/commit/b78ec0824da857223486660177d3b1f255c65d87
https://security.netapp.com/advisory/ntap-20240712-0005/
https://www.openssl.org/news/secadv/20240627.txt
http://www.openwall.com/lists/oss-security/2024/06/27/1
http://www.openwall.com/lists/oss-security/2024/06/28/4
http://www.openwall.com/lists/oss-security/2024/08/15/1
https://github.com/openssl/openssl/commit/4ada436a1946cbb24db5ab4ca082b69c1bc10f37
https://github.com/openssl/openssl/commit/99fb785a5f85315b95288921a321a935ea29a51e
https://github.com/openssl/openssl/commit/cf6f91f6121f4db167405db2f0de410a456f260c
https://github.com/openssl/openssl/commit/e86ac436f0bd54d4517745483e2315650fae7b2c
https://github.openssl.org/openssl/extended-releases/commit/9947251413065a05189a63c9b7a6c1d4e224c21c
https://github.openssl.org/openssl/extended-releases/commit/b78ec0824da857223486660177d3b1f255c65d87
https://security.netapp.com/advisory/ntap-20240712-0005/
https://www.openssl.org/news/secadv/20240627.txt
Configurations

No configuration.

History

21 Nov 2024, 09:47

Type Values Removed Values Added
References
  • () http://www.openwall.com/lists/oss-security/2024/08/15/1 -
References () http://www.openwall.com/lists/oss-security/2024/06/27/1 - () http://www.openwall.com/lists/oss-security/2024/06/27/1 -
References () http://www.openwall.com/lists/oss-security/2024/06/28/4 - () http://www.openwall.com/lists/oss-security/2024/06/28/4 -
References () https://github.com/openssl/openssl/commit/4ada436a1946cbb24db5ab4ca082b69c1bc10f37 - () https://github.com/openssl/openssl/commit/4ada436a1946cbb24db5ab4ca082b69c1bc10f37 -
References () https://github.com/openssl/openssl/commit/99fb785a5f85315b95288921a321a935ea29a51e - () https://github.com/openssl/openssl/commit/99fb785a5f85315b95288921a321a935ea29a51e -
References () https://github.com/openssl/openssl/commit/cf6f91f6121f4db167405db2f0de410a456f260c - () https://github.com/openssl/openssl/commit/cf6f91f6121f4db167405db2f0de410a456f260c -
References () https://github.com/openssl/openssl/commit/e86ac436f0bd54d4517745483e2315650fae7b2c - () https://github.com/openssl/openssl/commit/e86ac436f0bd54d4517745483e2315650fae7b2c -
References () https://github.openssl.org/openssl/extended-releases/commit/9947251413065a05189a63c9b7a6c1d4e224c21c - () https://github.openssl.org/openssl/extended-releases/commit/9947251413065a05189a63c9b7a6c1d4e224c21c -
References () https://github.openssl.org/openssl/extended-releases/commit/b78ec0824da857223486660177d3b1f255c65d87 - () https://github.openssl.org/openssl/extended-releases/commit/b78ec0824da857223486660177d3b1f255c65d87 -
References () https://security.netapp.com/advisory/ntap-20240712-0005/ - () https://security.netapp.com/advisory/ntap-20240712-0005/ -
References () https://www.openssl.org/news/secadv/20240627.txt - () https://www.openssl.org/news/secadv/20240627.txt -

12 Jul 2024, 14:15

Type Values Removed Values Added
References
  • () https://security.netapp.com/advisory/ntap-20240712-0005/ -

03 Jul 2024, 02:09

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CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 9.1

28 Jun 2024, 19:15

Type Values Removed Values Added
References
  • () http://www.openwall.com/lists/oss-security/2024/06/28/4 -
Summary
  • (es) Resumen del problema: llamar a la función API de OpenSSL SSL_select_next_proto con un búfer de protocolos de cliente compatible vacío puede provocar una falla o que se envíe contenido de la memoria al igual. Resumen de impacto: una lectura excesiva del búfer puede tener una variedad de consecuencias potenciales, como un comportamiento inesperado de la aplicación o un bloqueo. En particular, este problema podría provocar que se envíen hasta 255 bytes de datos privados arbitrarios de la memoria al par, lo que provocaría una pérdida de confidencialidad. Sin embargo, este problema solo afecta a las aplicaciones que llaman directamente a la función SSL_select_next_proto con una lista de longitud 0 de protocolos de cliente compatibles. Normalmente, esto nunca sería un escenario válido y normalmente no está bajo el control de un atacante, pero puede ocurrir por accidente en el caso de un error de configuración o programación en la aplicación que realiza la llamada. La función API de OpenSSL SSL_select_next_proto suele ser utilizada por aplicaciones TLS que admiten ALPN (negociación de protocolo de capa de aplicación) o NPN (negociación de siguiente protocolo). NPN es más antiguo, nunca se estandarizó y está en desuso en favor de ALPN. Creemos que ALPN está mucho más implementado que NPN. La función SSL_select_next_proto acepta una lista de protocolos del servidor y una lista de protocolos del cliente y devuelve el primer protocolo que aparece en la lista de servidores que también aparece en la lista de clientes. En caso de que no haya superposición entre las dos listas, devuelve el primer elemento de la lista de clientes. En cualquier caso, indicará si se encontró una superposición entre las dos listas. En el caso de que se llame a SSL_select_next_proto con una lista de clientes de longitud cero, no detecta esta condición y devuelve la memoria inmediatamente después del puntero de la lista de clientes (e informa que no hubo superposición en las listas). Esta función normalmente se llama desde una devolución de llamada de la aplicación del lado del servidor para ALPN o una devolución de llamada de la aplicación del lado del cliente para NPN. En el caso de ALPN, libssl garantiza que la lista de protocolos proporcionados por el cliente nunca tendrá una longitud cero. La lista de protocolos del servidor proviene de la aplicación y normalmente nunca se debe esperar que tenga una longitud cero. En este caso, si la función SSL_select_next_proto se llamó como se esperaba (con la lista proporcionada por el cliente pasada en los parámetros client/client_len), entonces la aplicación no será vulnerable a este problema. Si la aplicación se configuró accidentalmente con una lista de servidores de longitud cero y accidentalmente pasó esa lista de servidores de longitud cero en los parámetros client/client_len y además no pudo manejar correctamente una respuesta "sin superposición" (que normalmente daría como resultado una falla en el protocolo de enlace en ALPN) entonces será vulnerable a este problema. En el caso de NPN, el protocolo permite al cliente seleccionar de manera oportunista un protocolo cuando no hay superposición. OpenSSL devuelve el primer protocolo de cliente en el caso de que no haya superposición para respaldar esto. La lista de protocolos de cliente proviene de la aplicación y normalmente nunca se debe esperar que tenga una longitud cero. Sin embargo, si la función SSL_select_next_proto se llama accidentalmente con un client_len de 0, se devolverá un puntero de memoria no válido. Si la aplicación utiliza esta salida como protocolo oportunista, se producirá la pérdida de confidencialidad. Este problema se ha evaluado como de gravedad baja porque es más probable que las aplicaciones sean vulnerables si utilizan NPN en lugar de ALPN, pero NPN no se utiliza ampliamente. También requiere una configuración de la aplicación o un error de programación.-- truncada---

27 Jun 2024, 17:15

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References
  • () http://www.openwall.com/lists/oss-security/2024/06/27/1 -

27 Jun 2024, 11:15

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New CVE

Information

Published : 2024-06-27 11:15

Updated : 2024-11-21 09:47


NVD link : CVE-2024-5535

Mitre link : CVE-2024-5535

CVE.ORG link : CVE-2024-5535


JSON object : View

Products Affected

No product.

CWE
CWE-200

Exposure of Sensitive Information to an Unauthorized Actor