A vulnerability has been discovered in the iPXE open source project (CVE-2022-4087), which is utilized across numerous operating systems and platforms for booting over a network. This vulnerability has been classified as problematic, and it is highly recommended that users apply the appropriate patch to mitigate the potential risk. This post will provide an overview of the vulnerability, detail the affected components, and outline the steps necessary to apply the patch. There will also be a brief code snippet highlighting the vulnerability, links to the original references, and information on the exploit details.

Details

The vulnerability in question pertains to the handling of "pad_len" arguments in the function "tls_new_ciphertext" located within the "src/net/tls.c" file of iPXE. The affected component is the Transport Layer Security (TLS), which provides essential cryptographic functions that protect sensitive data over networks. By manipulating the "pad_len" argument, an attacker could potentially expose sensitive information by exploiting the discrepancy in the system.

Mitigation

The iPXE development team has released patch 186306d6199096b7a7c4b4574d4be8cdb8426729 to address this vulnerability. Applying this patch as soon as possible is strongly recommended to prevent potential exploits. To do so, users should obtain the appropriate patch from the iPXE repository and follow the standard procedure for applying patches to their systems.

Code Snippet

The affected code is located in "src/net/tls.c" of the iPXE project. The vulnerability arises due to improper handling of the "pad_len" argument in the "tls_new_ciphertext" function.

static void tls_new_ciphertext ( struct tls_connection *tls, size_t pad_len ) {
    ...
    tls->padding_length = pad_len;
    ...
}

For further information, please consult the official references regarding this vulnerability

1. iPXE Repository: https://github.com/ipxe/ipxe
2. Patch 186306d6199096b7a7c4b4574d4be8cdb8426729: https://github.com/ipxe/ipxe/commit/186306d6199096b7a7c4b4574d4be8cdb8426729

Exploit Details

Vulnerability Database Identifier (VDB-214054) has been assigned to this vulnerability. While there are no known active exploits in the wild at the time of this post, users should remain vigilant and apply the appropriate patch as soon as possible to ensure that their systems are protected.

Conclusion

In summary, CVE-2022-4087 is a problematic vulnerability in iPXE, potentially leading to information exposure through discrepancy in the TLS component. Users are strongly advised to apply patch 186306d6199096b7a7c4b4574d4be8cdb8426729 as soon as possible to mitigate this risk. Be sure to stay up to date on the latest security advisories and remain vigilant to keep your systems protected from potential threats.

Timeline

Published on: 11/21/2022 07:15:00 UTC
Last modified on: 02/03/2023 14:38:00 UTC