5.9
MEDIUM
CVE-2023-6237
OpenSSL RSA Public Key Checker Denial of Service Vulnerability
Description

Issue summary: Checking excessively long invalid RSA public keys may take a long time. Impact summary: Applications that use the function EVP_PKEY_public_check() to check RSA public keys may experience long delays. Where the key that is being checked has been obtained from an untrusted source this may lead to a Denial of Service. When function EVP_PKEY_public_check() is called on RSA public keys, a computation is done to confirm that the RSA modulus, n, is composite. For valid RSA keys, n is a product of two or more large primes and this computation completes quickly. However, if n is an overly large prime, then this computation would take a long time. An application that calls EVP_PKEY_public_check() and supplies an RSA key obtained from an untrusted source could be vulnerable to a Denial of Service attack. The function EVP_PKEY_public_check() is not called from other OpenSSL functions however it is called from the OpenSSL pkey command line application. For that reason that application is also vulnerable if used with the '-pubin' and '-check' options on untrusted data. The OpenSSL SSL/TLS implementation is not affected by this issue. The OpenSSL 3.0 and 3.1 FIPS providers are affected by this issue.

INFO

Published Date :

April 25, 2024, 7:15 a.m.

Last Modified :

Nov. 21, 2024, 8:43 a.m.

Remotely Exploitable :

Yes !

Impact Score :

3.6

Exploitability Score :

2.2
Public PoC/Exploit Available at Github

CVE-2023-6237 has a 5 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

Affected Products

The following products are affected by CVE-2023-6237 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Openssl openssl

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Fluentbit container image built as small as possible with security in mind

docker-image dockerfile fluent-bit

Dockerfile

Updated: 2 months ago
0 stars 0 fork 0 watcher
Born at : Oct. 22, 2024, 8:40 a.m. This repo has been linked 42 different CVEs too.

Container Vulnerability Analysis tooling

Dockerfile Shell

Updated: 6 months, 1 week ago
0 stars 0 fork 0 watcher
Born at : June 10, 2024, 3:01 p.m. This repo has been linked 7 different CVEs too.

None

HCL

Updated: 7 months, 2 weeks ago
0 stars 0 fork 0 watcher
Born at : April 30, 2024, 7:53 p.m. This repo has been linked 54 different CVEs too.

A centralized repository of standalone security patches for open source libraries.

appsec backport cve devsecops fix hotfix open-source patch protection remediation seal security update upgrade vulnerability

Updated: 5 months, 3 weeks ago
182 stars 0 fork 0 watcher
Born at : July 30, 2023, 4:46 p.m. This repo has been linked 265 different CVEs too.

None

Updated: 2 weeks, 2 days ago
6 stars 0 fork 0 watcher
Born at : Feb. 23, 2023, 5:42 a.m. This repo has been linked 462 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2023-6237 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2023-6237 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference http://www.openwall.com/lists/oss-security/2024/03/11/1
    Added Reference https://github.com/openssl/openssl/commit/0b0f7abfb37350794a4b8960fafc292cd5d1b84d
    Added Reference https://github.com/openssl/openssl/commit/18c02492138d1eb8b6548cb26e7b625fb2414a2a
    Added Reference https://github.com/openssl/openssl/commit/a830f551557d3d66a84bbb18a5b889c640c36294
    Added Reference https://security.netapp.com/advisory/ntap-20240531-0007/
    Added Reference https://www.openssl.org/news/secadv/20240115.txt
  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Nov. 01, 2024

    Action Type Old Value New Value
    Added CVSS V3.1 CISA-ADP AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
  • CVE Modified by [email protected]

    Oct. 14, 2024

    Action Type Old Value New Value
    Removed Reference OpenSSL Software Foundation http://www.openwall.com/lists/oss-security/2024/03/11/1
    Removed Reference OpenSSL Software Foundation https://security.netapp.com/advisory/ntap-20240531-0007/
    Added CWE OpenSSL Software Foundation CWE-606
  • CVE Modified by [email protected]

    Jun. 10, 2024

    Action Type Old Value New Value
    Added Reference OpenSSL Software Foundation https://security.netapp.com/advisory/ntap-20240531-0007/ [No types assigned]
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    May. 01, 2024

    Action Type Old Value New Value
    Added Reference OpenSSL Software Foundation http://www.openwall.com/lists/oss-security/2024/03/11/1 [No types assigned]
  • CVE Received by [email protected]

    Apr. 25, 2024

    Action Type Old Value New Value
    Added Description Issue summary: Checking excessively long invalid RSA public keys may take a long time. Impact summary: Applications that use the function EVP_PKEY_public_check() to check RSA public keys may experience long delays. Where the key that is being checked has been obtained from an untrusted source this may lead to a Denial of Service. When function EVP_PKEY_public_check() is called on RSA public keys, a computation is done to confirm that the RSA modulus, n, is composite. For valid RSA keys, n is a product of two or more large primes and this computation completes quickly. However, if n is an overly large prime, then this computation would take a long time. An application that calls EVP_PKEY_public_check() and supplies an RSA key obtained from an untrusted source could be vulnerable to a Denial of Service attack. The function EVP_PKEY_public_check() is not called from other OpenSSL functions however it is called from the OpenSSL pkey command line application. For that reason that application is also vulnerable if used with the '-pubin' and '-check' options on untrusted data. The OpenSSL SSL/TLS implementation is not affected by this issue. The OpenSSL 3.0 and 3.1 FIPS providers are affected by this issue.
    Added Reference OpenSSL Software Foundation https://www.openssl.org/news/secadv/20240115.txt [No types assigned]
    Added Reference OpenSSL Software Foundation https://github.com/openssl/openssl/commit/18c02492138d1eb8b6548cb26e7b625fb2414a2a [No types assigned]
    Added Reference OpenSSL Software Foundation https://github.com/openssl/openssl/commit/a830f551557d3d66a84bbb18a5b889c640c36294 [No types assigned]
    Added Reference OpenSSL Software Foundation https://github.com/openssl/openssl/commit/0b0f7abfb37350794a4b8960fafc292cd5d1b84d [No types assigned]
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2023-6237 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2023-6237 weaknesses.

CVSS31 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability