libcurl-using applications can ask for a specific client certificate to be used in a transfer. This is done with the `CURLOPT_SSLCERT` option (`--cert` with the command line tool).When libcurl is built to use the macOS native TLS library Secure Transport, an application can ask for the client certificate by name or with a file name - using the same option. If the name exists as a file, it will be used instead of by name.If the appliction runs with a current working directory that is writable by other users (like `/tmp`), a malicious user can create a file name with the same name as the app wants to use by name, and thereby trick the application to use the file based cert instead of the one referred to by name making libcurl send the wrong client certificate in the TLS connection handshake.

The remote host is affected by the vulnerability described in GLSA-202212-01 (curl: Multiple Vulnerabilities)

  - When curl is instructed to download content using the metalink feature, thecontents is verified against a     hash provided in the metalink XML file.The metalink XML file points out to the client how to get the same     contentfrom a set of different URLs, potentially hosted by different servers and theclient can then     download the file from one or several of them. In a serial orparallel manner.If one of the servers hosting     the contents has been breached and the contentsof the specific file on that server is replaced with a     modified payload, curlshould detect this when the hash of the file mismatches after a completeddownload.
    It should remove the contents and instead try getting the contentsfrom another URL. This is not done, and     instead such a hash mismatch is onlymentioned in text and the potentially malicious content is kept in the     file ondisk. (CVE-2021-22922)

  - When curl is instructed to get content using the metalink feature, and a user name and password are used     to download the metalink XML file, those same credentials are then subsequently passed on to each of the     servers from which curl will download or try to download the contents from. Often contrary to the user's     expectations and intentions and without telling the user it happened. (CVE-2021-22923)

  - curl supports the `-t` command line option, known as `CURLOPT_TELNETOPTIONS`in libcurl. This rarely used     option is used to send variable=content pairs toTELNET servers.Due to flaw in the option parser for     sending `NEW_ENV` variables, libcurlcould be made to pass on uninitialized data from a stack based buffer     to theserver. Therefore potentially revealing sensitive internal information to theserver using a clear-     text network protocol.This could happen because curl did not call and use sscanf() correctly whenparsing     the string provided by the application. (CVE-2021-22925)

  - libcurl-using applications can ask for a specific client certificate to be used in a transfer. This is     done with the `CURLOPT_SSLCERT` option (`--cert` with the command line tool).When libcurl is built to use     the macOS native TLS library Secure Transport, an application can ask for the client certificate by name     or with a file name - using the same option. If the name exists as a file, it will be used instead of by     name.If the appliction runs with a current working directory that is writable by other users (like     `/tmp`), a malicious user can create a file name with the same name as the app wants to use by name, and     thereby trick the application to use the file based cert instead of the one referred to by name making     libcurl send the wrong client certificate in the TLS connection handshake. (CVE-2021-22926)

  - When sending data to an MQTT server, libcurl <= 7.73.0 and 7.78.0 could in some circumstances erroneously     keep a pointer to an already freed memory area and both use that again in a subsequent call to send data     and also free it *again*. (CVE-2021-22945)

  - 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. (CVE-2021-22946)

  - 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. (CVE-2021-22947)

  - An improper authentication vulnerability exists in curl 7.33.0 to and including 7.82.0 which might allow     reuse OAUTH2-authenticated connections without properly making sure that the connection was authenticated     with the same credentials as set for this transfer. This affects SASL-enabled protocols: SMPTP(S),     IMAP(S), POP3(S) and LDAP(S) (openldap only). (CVE-2022-22576)

  - An insufficiently protected credentials vulnerability exists in curl 4.9 to and include curl 7.82.0 are     affected that could allow an attacker to extract credentials when follows HTTP(S) redirects is used with     authentication could leak credentials to other services that exist on different protocols or port numbers.
    (CVE-2022-27774)

  - An information disclosure vulnerability exists in curl 7.65.0 to 7.82.0 are vulnerable that by using an     IPv6 address that was in the connection pool but with a different zone id it could reuse a connection     instead. (CVE-2022-27775)

  - A insufficiently protected credentials vulnerability in fixed in curl 7.83.0 might leak authentication or     cookie header data on HTTP redirects to the same host but another port number. (CVE-2022-27776)

  - libcurl wrongly allows cookies to be set for Top Level Domains (TLDs) if thehost name is provided with a     trailing dot.curl can be told to receive and send cookies. curl's cookie engine can bebuilt with or     without [Public Suffix List](https://publicsuffix.org/)awareness. If PSL support not provided, a more     rudimentary check exists to atleast prevent cookies from being set on TLDs. This check was broken if     thehost name in the URL uses a trailing dot.This can allow arbitrary sites to set cookies that then would     get sent to adifferent and unrelated site or domain. (CVE-2022-27779)

  - The curl URL parser wrongly accepts percent-encoded URL separators like '/'when decoding the host name     part of a URL, making it a *different* URL usingthe wrong host name when it is later retrieved.For     example, a URL like `http://example.com%2F127.0.0.1/`, would be allowed bythe parser and get transposed     into `http://example.com/127.0.0.1/`. This flawcan be used to circumvent filters, checks and more.
    (CVE-2022-27780)

  - libcurl provides the `CURLOPT_CERTINFO` option to allow applications torequest details to be returned     about a server's certificate chain.Due to an erroneous function, a malicious server could make libcurl     built withNSS get stuck in a never-ending busy-loop when trying to retrieve thatinformation.
    (CVE-2022-27781)

  - libcurl would reuse a previously created connection even when a TLS or SSHrelated option had been changed     that should have prohibited reuse.libcurl keeps previously used connections in a connection pool for     subsequenttransfers to reuse if one of them matches the setup. However, several TLS andSSH settings were     left out from the configuration match checks, making themmatch too easily. (CVE-2022-27782)

  - Using its HSTS support, curl can be instructed to use HTTPS directly insteadof using an insecure clear-     text HTTP step even when HTTP is provided in theURL. This mechanism could be bypassed if the host name in     the given URL used atrailing dot while not using one when it built the HSTS cache. Or the otherway around
    - by having the trailing dot in the HSTS cache and *not* using thetrailing dot in the URL.
    (CVE-2022-30115)

  - A malicious server can serve excessive amounts of `Set-Cookie:` headers in a HTTP response to curl and     curl < 7.84.0 stores all of them. A sufficiently large amount of (big) cookies make subsequent HTTP     requests to this, or other servers to which the cookies match, create requests that become larger than the     threshold that curl uses internally to avoid sending crazy large requests (1048576 bytes) and instead     returns an error.This denial state might remain for as long as the same cookies are kept, match and     haven't expired. Due to cookie matching rules, a server on `foo.example.com` can set cookies that also     would match for `bar.example.com`, making it it possible for a sister server to effectively cause a     denial of service for a sibling site on the same second level domain using this method. (CVE-2022-32205)

  - curl < 7.84.0 supports chained HTTP compression algorithms, meaning that a serverresponse can be     compressed multiple times and potentially with different algorithms. The number of acceptable links in     this decompression chain was unbounded, allowing a malicious server to insert a virtually unlimited     number of compression steps.The use of such a decompression chain could result in a malloc bomb,     makingcurl end up spending enormous amounts of allocated heap memory, or trying toand returning out of     memory errors. (CVE-2022-32206)

  - When curl < 7.84.0 saves cookies, alt-svc and hsts data to local files, it makes the operation atomic by     finalizing the operation with a rename from a temporary name to the final target file name.In that rename     operation, it might accidentally *widen* the permissions for the target file, leaving the updated file     accessible to more users than intended. (CVE-2022-32207)

  - When curl < 7.84.0 does FTP transfers secured by krb5, it handles message verification failures wrongly.
    This flaw makes it possible for a Man-In-The-Middle attack to go unnoticed and even allows it to inject     data to the client. (CVE-2022-32208)

  - When doing HTTP(S) transfers, libcurl might erroneously use the read callback (`CURLOPT_READFUNCTION`) to     ask for data to send, even when the `CURLOPT_POSTFIELDS` option has been set, if the same handle     previously was used to issue a `PUT` request which used that callback. This flaw may surprise the     application and cause it to misbehave and either send off the wrong data or use memory after free or     similar in the subsequent `POST` request. The problem exists in the logic for a reused handle when it is     changed from a PUT to a POST. (CVE-2022-32221)

  - When curl is used to retrieve and parse cookies from a HTTP(S) server, itaccepts cookies using control     codes that when later are sent back to a HTTPserver might make the server return 400 responses.
    Effectively allowing asister site to deny service to all siblings. (CVE-2022-35252)

  - curl can be told to parse a `.netrc` file for credentials. If that file endsin a line with 4095     consecutive non-white space letters and no newline, curlwould first read past the end of the stack-based     buffer, and if the readworks, write a zero byte beyond its boundary.This will in most cases cause a     segfault or similar, but circumstances might also cause different outcomes.If a malicious user can provide     a custom netrc file to an application or otherwise affect its contents, this flaw could be used as denial-     of-service. (CVE-2022-35260)

  - curl before 7.86.0 has a double free. If curl is told to use an HTTP proxy for a transfer with a non-     HTTP(S) URL, it sets up the connection to the remote server by issuing a CONNECT request to the proxy, and     then tunnels the rest of the protocol through. An HTTP proxy might refuse this request (HTTP proxies often     only allow outgoing connections to specific port numbers, like 443 for HTTPS) and instead return a non-200     status code to the client. Due to flaws in the error/cleanup handling, this could trigger a double free in     curl if one of the following schemes were used in the URL for the transfer: dict, gopher, gophers, ldap,     ldaps, rtmp, rtmps, or telnet. The earliest affected version is 7.77.0. (CVE-2022-42915)

  - In curl before 7.86.0, the HSTS check could be bypassed to trick it into staying with HTTP. Using its HSTS     support, curl can be instructed to use HTTPS directly (instead of using an insecure cleartext HTTP step)     even when HTTP is provided in the URL. This mechanism could be bypassed if the host name in the given URL     uses IDN characters that get replaced with ASCII counterparts as part of the IDN conversion, e.g., using     the character UTF-8 U+3002 (IDEOGRAPHIC FULL STOP) instead of the common ASCII full stop of U+002E (.).
    The earliest affected version is 7.77.0 2021-05-26. (CVE-2022-42916)

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

According to the versions of the curl packages installed, the EulerOS Virtualization installation on the remote host is affected by the following vulnerabilities :

  - When curl is instructed to download content using the metalink feature, thecontents is verified against a     hash provided in the metalink XML file.The metalink XML file points out to the client how to get the same     contentfrom a set of different URLs, potentially hosted by different servers and theclient can then     download the file from one or several of them. In a serial orparallel manner.If one of the servers hosting     the contents has been breached and the contentsof the specific file on that server is replaced with a     modified payload, curlshould detect this when the hash of the file mismatches after a completeddownload.
    It should remove the contents and instead try getting the contentsfrom another URL. This is not done, and     instead such a hash mismatch is onlymentioned in text and the potentially malicious content is kept in the     file ondisk. (CVE-2021-22922)

  - When curl is instructed to get content using the metalink feature, and a user name and password are used     to download the metalink XML file, those same credentials are then subsequently passed on to each of the     servers from which curl will download or try to download the contents from. Often contrary to the user's     expectations and intentions and without telling the user it happened. (CVE-2021-22923)

  - libcurl keeps previously used connections in a connection pool for subsequenttransfers to reuse, if one of     them matches the setup.Due to errors in the logic, the config matching function did not take 'issuercert'     into account and it compared the involved paths *case insensitively*,which could lead to libcurl reusing     wrong connections.File paths are, or can be, case sensitive on many systems but not all, and caneven vary     depending on used file systems.The comparison also didn't include the 'issuer cert' which a transfer can     setto qualify how to verify the server certificate. (CVE-2021-22924)

  - curl supports the `-t` command line option, known as `CURLOPT_TELNETOPTIONS`in libcurl. This rarely used     option is used to send variable=content pairs toTELNET servers.Due to flaw in the option parser for     sending `NEW_ENV` variables, libcurlcould be made to pass on uninitialized data from a stack based buffer     to theserver. Therefore potentially revealing sensitive internal information to theserver using a clear-     text network protocol.This could happen because curl did not call and use sscanf() correctly whenparsing     the string provided by the application. (CVE-2021-22925)

  - libcurl-using applications can ask for a specific client certificate to be used in a transfer. This is     done with the `CURLOPT_SSLCERT` option (`--cert` with the command line tool).When libcurl is built to use     the macOS native TLS library Secure Transport, an application can ask for the client certificate by name     or with a file name - using the same option. If the name exists as a file, it will be used instead of by     name.If the appliction runs with a current working directory that is writable by other users (like     `/tmp`), a malicious user can create a file name with the same name as the app wants to use by name, and     thereby trick the application to use the file based cert instead of the one referred to by name making     libcurl send the wrong client certificate in the TLS connection handshake. (CVE-2021-22926)

Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

According to the versions of the curl packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities :

  - When curl is instructed to download content using the metalink feature, thecontents is verified against a     hash provided in the metalink XML file.The metalink XML file points out to the client how to get the same     contentfrom a set of different URLs, potentially hosted by different servers and theclient can then     download the file from one or several of them. In a serial orparallel manner.If one of the servers hosting     the contents has been breached and the contentsof the specific file on that server is replaced with a     modified payload, curlshould detect this when the hash of the file mismatches after a completeddownload.
    It should remove the contents and instead try getting the contentsfrom another URL. This is not done, and     instead such a hash mismatch is onlymentioned in text and the potentially malicious content is kept in the     file ondisk. (CVE-2021-22922)

  - When curl is instructed to get content using the metalink feature, and a user name and password are used     to download the metalink XML file, those same credentials are then subsequently passed on to each of the     servers from which curl will download or try to download the contents from. Often contrary to the user's     expectations and intentions and without telling the user it happened. (CVE-2021-22923)

  - libcurl keeps previously used connections in a connection pool for subsequenttransfers to reuse, if one of     them matches the setup.Due to errors in the logic, the config matching function did not take 'issuercert'     into account and it compared the involved paths *case insensitively*,which could lead to libcurl reusing     wrong connections.File paths are, or can be, case sensitive on many systems but not all, and caneven vary     depending on used file systems.The comparison also didn't include the 'issuer cert' which a transfer can     setto qualify how to verify the server certificate. (CVE-2021-22924)

  - curl supports the `-t` command line option, known as `CURLOPT_TELNETOPTIONS`in libcurl. This rarely used     option is used to send variable=content pairs toTELNET servers.Due to flaw in the option parser for     sending `NEW_ENV` variables, libcurlcould be made to pass on uninitialized data from a stack based buffer     to theserver. Therefore potentially revealing sensitive internal information to theserver using a clear-     text network protocol.This could happen because curl did not call and use sscanf() correctly whenparsing     the string provided by the application. (CVE-2021-22925)

  - libcurl-using applications can ask for a specific client certificate to be used in a transfer. This is     done with the `CURLOPT_SSLCERT` option (`--cert` with the command line tool).When libcurl is built to use     the macOS native TLS library Secure Transport, an application can ask for the client certificate by name     or with a file name - using the same option. If the name exists as a file, it will be used instead of by     name.If the appliction runs with a current working directory that is writable by other users (like     `/tmp`), a malicious user can create a file name with the same name as the app wants to use by name, and     thereby trick the application to use the file based cert instead of the one referred to by name making     libcurl send the wrong client certificate in the TLS connection handshake. (CVE-2021-22926)

Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

The version of MySQL running on the remote host is 5.7.x prior to 5.7.36. It is, therefore, affected by multiple vulnerabilities, including the following, as noted in the October 2021 Critical Patch Update advisory:

  - A vulnerability in the OpenSSL component that can result in a takeover of the MySQL server.
    (CVE-2021-3711)

  - An easily exploitable vulnerability in the InnoDB component that allows a high privileged attacker to     affect the integrity and availability of the MySQL Server. (CVE-2021-35604)

  - An easily exploitable vulnerability in the cURL component that allows an unauthenticated, remote attacker     to affect the availability of the MySQL Server. (CVE-2021-22926)

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

The version of MySQL running on the remote host is 8.0.x prior to 8.0.27. It is, therefore, affected by multiple vulnerabilities, including the following, as noted in the October 2021 Critical Patch Update advisory:

  - A vulnerability in the OpenSSL component that can result in a takeover of the MySQL server.
    (CVE-2021-3711)

  - An easily exploitable vulnerability in the Kerberos component of MySQL server that allows an     unauthenticated, remote attacker to affect availability. (CVE-2021-36222)

  - An easily exploitable vulnerability in the cURL component that allows an unauthenticated, remote attacker     to affect the availability of the MySQL Server. (CVE-2021-22926)

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

The cURL project reports :

CURLOPT_SSLCERT mixup with Secure Transport (CVE-2021-22926)

TELNET stack contents disclosure again (CVE-2021-22925)

Bad connection reuse due to flawed path name checks (CVE-2021-92254)

Metalink download sends credentials (CVE-2021-92253)

Wrong content via metalink not discarded (CVE-2021-92252)

New curl packages are available for Slackware 14.0, 14.1, 14.2, and
-current to fix security issues.

ID	Name	Product	Family	Severity
168911	GLSA-202212-01 : curl: Multiple Vulnerabilities	Nessus	Gentoo Local Security Checks	critical
155491	EulerOS Virtualization 2.9.0 : curl (EulerOS-SA-2021-2769)	Nessus	Huawei Local Security Checks	medium
155489	EulerOS Virtualization 2.9.1 : curl (EulerOS-SA-2021-2751)	Nessus	Huawei Local Security Checks	medium
155263	EulerOS 2.0 SP9 : curl (EulerOS-SA-2021-2707)	Nessus	Huawei Local Security Checks	medium
155117	EulerOS 2.0 SP9 : curl (EulerOS-SA-2021-2682)	Nessus	Huawei Local Security Checks	medium
154259	MySQL 5.7.x < 5.7.36 Multiple Vulnerabilities (Oct 2021 CPU)	Nessus	Databases	critical
154258	MySQL 8.0.x < 8.0.27 Multiple Vulnerabilities (Oct 2021 CPU)	Nessus	Databases	critical
151971	FreeBSD : cURL -- Multiple vulnerabilities (aa646c01-ea0d-11eb-9b84-d4c9ef517024)	Nessus	FreeBSD Local Security Checks	medium
151970	Slackware 14.0 / 14.1 / 14.2 / current : curl (SSA:2021-202-02)	Nessus	Slackware Local Security Checks	medium

Detections

Analytics

CVE-2021-22926

high

Tenable Plugins

critical

medium

medium

medium

medium

critical

critical

medium

medium