It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2023-193 advisory.

    The curl advisory describes this issue as follows:

    curl supports communicating using the TELNET protocol and as a part of this it offers users to pass on     user name and telnet options for the server negotiation.

    Due to lack of proper input scrubbing and without it being the documented functionality, curl would pass     on user name and telnet options to the server as provided. This could allow users to pass in carefully     crafted content that pass on content or do option negotiation without the application intending to do so.
    In particular if an application for example allows users to provide the data or parts of the data.
    (CVE-2023-27533)

    The curl advisory describes this issue as follows:

    curl supports SFTP transfers. curl's SFTP implementation offers a special feature in the path component of     URLs: a tilde (~) character as the first path element in the path to denotes a path relative to the user's     home directory. This is supported because of wording in the once proposed to-become RFC draft that was to     dictate how SFTP URLs work.

    Due to a bug, the handling of the tilde in SFTP path did however not only replace it when it is used     stand-alone as the first path element but also wrongly when used as a mere prefix in the first element.

    Using a path like /~2/foo when accessing a server using the user dan (with home directory /home/dan) would     then quite surprisingly access the file /home/dan2/foo.

    This can be taken advantage of to circumvent filtering or worse. (CVE-2023-27534)

    The curl advisory describes this issue as follows:

    libcurl would reuse a previously created FTP connection even when one or more options had been changed     that could have made the effective user a very different one, thus leading to the doing the second     transfer with wrong credentials. (CVE-2023-27535)

    The curl advisory describes this issue as follows:

    libcurl would reuse a previously created connection even when the GSS delegation     (CURLOPT_GSSAPI_DELEGATION) option had been changed that could have changed the user's permissions in a     second transfer.

    libcurl keeps previously used connections in a connection pool for subsequent transfers to reuse if one of     them matches the setup. However, this GSS delegation setting was left out from the configuration match     checks, making them match too easily, affecting krb5/kerberos/negotiate/GSSAPI transfers. (CVE-2023-27536)

    The curl advisory describes this issue as follows:

    libcurl supports sharing HSTS data between separate handles. This sharing was introduced without     considerations for doing this sharing across separate threads, but there was no indication of this fact in     the documentation. Due to missing mutexes or thread locks, two threads sharing the same HSTS data could     end up doing a double-free or use-after-free. (CVE-2023-27537)

    The curl advisory describes this issue as follows:

    libcurl would reuse a previously created connection even when an SSH related option had been changed that     should have prohibited reuse.

    libcurl keeps previously used connections in a connection pool for subsequent transfers to reuse if one of     them matches the setup. However, two SSH settings were left out from the configuration match checks,     making them match too easily. (CVE-2023-27538)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Detections

Analytics

Amazon Linux 2023 : curl, curl-minimal, libcurl (ALAS2023-2023-193)

high Nessus Plugin ID 176898

Version 1.2

Version 1.1

Version 1.0

Version 1.2 Dec 12, 2024, 9:55 AM CVSS metrics ("Cvssv4 score" set to 0.0) CVSSv2 severity (based on None, severity decreased from "High" to "Low") Detection (updated detection logic) Plugin metadata Plugin Feed: 202412120955
Version 1.1 Jun 8, 2023, 9:25 PM Exploit attributes ("Exploitability ease" changed from "No known exploits are available" to "Exploits are available") Plugin Feed: 202306082125
Version 1.0 Jun 8, 2023, 8:30 AM New Plugin Feed: 202306080830