CVE-2023-6237
published 2024-04-25CVE-2023-6237: Issue summary: Checking excessively long invalid RSA public keys may take a long time. Impact summary: Applications that use the function…
PriorityP430medium5.9CVSS 3.1
AVNACHPRNUINSUCNINAH
EPSS
2.30%
81.5th percentile
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.
Affected
41 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | openssl | < openssl 3.0.13-1~deb12u1 (bookworm) | openssl 3.0.13-1~deb12u1 (bookworm) |
| haxx | curl | >= 0 < 7.81.0-1ubuntu1.13 | 7.81.0-1ubuntu1.13 |
| haxx | curl | >= 0 < 7.35.0-1ubuntu2.20+esm16 | 7.35.0-1ubuntu2.20+esm16 |
| haxx | curl | >= 0 < 7.47.0-1ubuntu2.19+esm9 | 7.47.0-1ubuntu2.19+esm9 |
| haxx | curl | >= 0 < 7.58.0-2ubuntu3.24+esm1 | 7.58.0-2ubuntu3.24+esm1 |
| msrc | azl3_cloud-hypervisor-cvm_38.0.72-2_on_azure_linux_3.0 | — | — |
| msrc | azl3_cloud-hypervisor-cvm_38.0.72.2-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_nodejs_20.10.0-2_on_azure_linux_3.0 | — | — |
| msrc | azl3_nodejs_20.14.0-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_openssl_3.1.4-9_on_azure_linux_3.0 | — | — |
| msrc | azl3_openssl_3.3.0-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_qemu_8.2.0-16_on_azure_linux_3.0 | — | — |
| msrc | azure_linux_3.0_arm | — | — |
| msrc | azure_linux_3.0_x64 | — | — |
| msrc | cbl2_cloud-hypervisor-cvm_38.0.72-1_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_cloud-hypervisor-cvm_38.0.72.2-1_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_hvloader_1.0.1-5_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_hvloader_1.0.1-6_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_nodejs18_18.18.2-7_on_cbl_mariner_2.0 | — | — |
| msrc | cbl2_nodejs18_18.20.2-1_on_cbl_mariner_2.0 | — | — |
| msrc | cbl_mariner_2.0_arm | — | — |
| msrc | cbl_mariner_2.0_x64 | — | — |
| openssl | openssl | >= 0 < 3.0.12-r3 | 3.0.12-r3 |
| openssl | openssl | >= 0 < 3.1.4-r4 | 3.1.4-r4 |
| openssl | openssl | >= 0 < 3.1.4-r4 | 3.1.4-r4 |
CVSS provenance
nvdv3.15.9MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
osv7.4HIGH
vendor_ubuntu7.4HIGH
vendor_debian5.9MEDIUM
vendor_msrc5.9MEDIUM
vendor_redhat5.9MEDIUM
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OSV
edk2 regression
osv·2025-11-28·CVSS 7.4
CVE-2023-45236 [HIGH] edk2 regression
edk2 regression
USN-7894-1 fixed vulnerabilities in EDK II. The update introduced a
regression in the UEFI network boot. This update reverts the corresponding
fixes for CVE-2023-45236 and CVE-2023-45237 pending further investigation.
We apologize for the inconvenience.
Original advisory details:
It was discovered that EDK II was susceptible to a predictable TCP Initial
Sequence Number. An attacker could possibly use this issue to gain
unauthorized access. This issue only affected Ubuntu 22.04 LTS, and Ubuntu
24.04 LTS. (CVE-2023-45236, CVE-2023-45237)
It was discovered that EDK II incorrectly handled S3 sleep. An attacker
could possibly use this issue to cause a denial of service. This issue only
affected Ubuntu 22.04 LTS, and Ubuntu 24.04 LTS. (CVE-2024-1298)
It was discovered that
OSV
edk2 vulnerabilities
osv·2025-11-26·CVSS 7.4
CVE-2023-45236 [HIGH] edk2 vulnerabilities
edk2 vulnerabilities
It was discovered that EDK II was susceptible to a predictable TCP Initial
Sequence Number. An attacker could possibly use this issue to gain
unauthorized access. This issue only affected Ubuntu 22.04 LTS, and Ubuntu
24.04 LTS. (CVE-2023-45236, CVE-2023-45237)
It was discovered that EDK II incorrectly handled S3 sleep. An attacker
could possibly use this issue to cause a denial of service. This issue only
affected Ubuntu 22.04 LTS, and Ubuntu 24.04 LTS. (CVE-2024-1298)
It was discovered that the EDK II PE/COFF loader incorrectly handled
certain memory operations. An attacker could possibly use this issue to
cause a denial of service, obtain sensitive information, or execute
arbitrary code. This issue only affected Ubuntu 22.04 LTS, and Ubuntu
24.04 LTS. (CVE-2024-38
OSV
CVE-2023-6237: Issue summary: Checking excessively long invalid RSA public keys may take a long time
osv·2024-04-25·CVSS 5.9
CVE-2023-6237 [MEDIUM] CVE-2023-6237: Issue summary: Checking excessively long invalid RSA public keys may take a long time
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
GHSA
GHSA-hvc4-mjv4-5mw6: Issue summary: Checking excessively long invalid RSA public keys may take
a long time
ghsa_unreviewed·2024-04-25
CVE-2023-6237 [MEDIUM] CWE-606 GHSA-hvc4-mjv4-5mw6: Issue summary: Checking excessively long invalid RSA public keys may take
a long time
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 Den
OSV
CVE-2023-6237: Issue summary: Checking excessively long invalid RSA public keys may take
a long time
osv·2024-04-25·CVSS 5.9
CVE-2023-6237 [MEDIUM] CVE-2023-6237: Issue summary: Checking excessively long invalid RSA public keys may take
a long time
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 Den
OSV
openssl vulnerabilities
osv·2024-02-05·CVSS 5.3
CVE-2023-5678 [MEDIUM] openssl vulnerabilities
openssl vulnerabilities
David Benjamin discovered that OpenSSL incorrectly handled excessively long
X9.42 DH keys. A remote attacker could possibly use this issue to cause
OpenSSL to consume resources, leading to a denial of service.
(CVE-2023-5678)
Sverker Eriksson discovered that OpenSSL incorrectly handled POLY1304 MAC
on the PowerPC architecture. A remote attacker could use this issue to
cause OpenSSL to crash, resulting in a denial of service, or possibly
execute arbitrary code. This issue only affected Ubuntu 22.04 LTS and
Ubuntu 23.04. (CVE-2023-6129)
It was discovered that OpenSSL incorrectly handled excessively long RSA
public keys. A remote attacker could possibly use this issue to cause
OpenSSL to consume resources, leading to a denial of service. This issue
only affected Ubu
OSV
curl vulnerabilities
osv·2023-09-11·CVSS 5.9
CVE-2023-28321 curl vulnerabilities
curl vulnerabilities
USN-6237-1 fixed several vulnerabilities in curl. This update provides the
corresponding updates for Ubuntu 14.04 LTS, Ubuntu 16.04 LTS, and
Ubuntu 18.04 LTS.
Original advisory details:
Hiroki Kurosawa discovered that curl incorrectly handled validating certain
certificate wildcards. A remote attacker could possibly use this issue to
spoof certain website certificates using IDN hosts. (CVE-2023-28321)
Hiroki Kurosawa discovered that curl incorrectly handled callbacks when
certain options are set by applications. This could cause applications
using curl to misbehave, resulting in information disclosure, or a denial
of service. (CVE-2023-28322)
It was discovered that curl incorrectly handled saving cookies to files. A
local attacker could possibly use this issue to
OSV
curl regression
osv·2023-07-19·CVSS 5.9
CVE-2023-28321 curl regression
curl regression
USN-6237-1 fixed vulnerabilities in curl. The update caused a certificate
wildcard handling regression on Ubuntu 22.04 LTS. This update fixes the
problem.
We apologize for the inconvenience.
Original advisory details:
Hiroki Kurosawa discovered that curl incorrectly handled validating certain
certificate wildcards. A remote attacker could possibly use this issue to
spoof certain website certificates using IDN hosts. (CVE-2023-28321)
Hiroki Kurosawa discovered that curl incorrectly handled callbacks when
certain options are set by applications. This could cause applications
using curl to misbehave, resulting in information disclosure, or a denial
of service. (CVE-2023-28322)
It was discovered that curl incorrectly handled saving cookies to files. A
local attacker could
Ubuntu
EDK II regression
vendor_ubuntu·2025-11-28·CVSS 5.8
CVE-2023-45236 [MEDIUM] EDK II regression
Title: EDK II regression
Summary: USN-7894-1 introduced a regression in EDK II
USN-7894-1 fixed vulnerabilities in EDK II. The update introduced a
regression in the UEFI network boot. This update reverts the corresponding
fixes for CVE-2023-45236 and CVE-2023-45237 pending further investigation.
We apologize for the inconvenience.
Original advisory details:
It was discovered that EDK II was susceptible to a predictable TCP Initial
Sequence Number. An attacker could possibly use this issue to gain
unauthorized access. This issue only affected Ubuntu 22.04 LTS, and Ubuntu
24.04 LTS. (CVE-2023-45236, CVE-2023-45237)
It was discovered that EDK II incorrectly handled S3 sleep. An attacker
could possibly use this issue to cause a denial of service. This issue only
affected Ubuntu 22.04 LTS
Ubuntu
EDK II vulnerabilities
vendor_ubuntu·2025-11-26·CVSS 7.4
CVE-2023-45236 [HIGH] EDK II vulnerabilities
Title: EDK II vulnerabilities
Summary: Several security issues were fixed in EDK II.
It was discovered that EDK II was susceptible to a predictable TCP Initial
Sequence Number. An attacker could possibly use this issue to gain
unauthorized access. This issue only affected Ubuntu 22.04 LTS, and Ubuntu
24.04 LTS. (CVE-2023-45236, CVE-2023-45237)
It was discovered that EDK II incorrectly handled S3 sleep. An attacker
could possibly use this issue to cause a denial of service. This issue only
affected Ubuntu 22.04 LTS, and Ubuntu 24.04 LTS. (CVE-2024-1298)
It was discovered that the EDK II PE/COFF loader incorrectly handled
certain memory operations. An attacker could possibly use this issue to
cause a denial of service, obtain sensitive information, or execute
arbitrary code. This issue o
CISA ICS
Siemens SCALANCE W700
cisa_ics·2025-02-13
Siemens SCALANCE W700
ICS Advisory
##
Siemens SCALANCE W700
Release DateFebruary 13, 2025
Alert CodeICSA-25-044-09
Related topics:
Industrial Control System Vulnerabilities, Industrial Control Systems
As of January 10, 2023, CISA will no longer be updating ICS security advisories for Siemens product vulnerabilities beyond the initial advisory. For the most up-to-date information on vulnerabilities in this advisory, please see Siemens' ProductCERT Security Advisories (CERT Services | Services | Siemens Global).
View CSAF
## 1. EXECUTIVE SUMMARY
- CVSS v3 9.8
- ATTENTION: Exploitable remotely/low attack complexity
- Vendor: Siemens
- Equipment: SCALANCE W700
- Vulnerabilities: Double Free, Improper Restriction of Communication Channel to Intended Endpoints, Improper Resource Sh
CISA ICS
Siemens SINEC NMS
cisa_ics·2024-11-14
Siemens SINEC NMS
ICS Advisory
##
Siemens SINEC NMS
Release DateNovember 14, 2024
Alert CodeICSA-24-319-04
Related topics:
Industrial Control System Vulnerabilities, Industrial Control Systems
As of January 10, 2023, CISA will no longer be updating ICS security advisories for Siemens product vulnerabilities beyond the initial advisory. For the most up-to-date information on vulnerabilities in this advisory, please see Siemens' ProductCERT Security Advisories (CERT Services | Services | Siemens Global).
View CSAF
## 1. EXECUTIVE SUMMARY
- CVSS v4 8.3
- ATTENTION: Exploitable remotely/low attack complexity
- Vendor: Siemens
- Equipment: SINEC NMS
- Vulnerabilities: Improper Input Validation, Improper Check for Unusual or Exceptional Conditions, Out-of-bounds Write, Uncontro
CISA ICS
Siemens SINEC INS
cisa_ics·2024-11-14
Siemens SINEC INS
ICS Advisory
##
Siemens SINEC INS
Release DateNovember 14, 2024
Alert CodeICSA-24-319-08
Related topics:
Industrial Control System Vulnerabilities, Industrial Control Systems
As of January 10, 2023, CISA will no longer be updating ICS security advisories for Siemens product vulnerabilities beyond the initial advisory. For the most up-to-date information on vulnerabilities in this advisory, please see Siemens' ProductCERT Security Advisories (CERT Services | Services | Siemens Global).
View CSAF
## 1. EXECUTIVE SUMMARY
- CVSS v3 9.9
- ATTENTION: Exploitable remotely/low attack complexity/public exploits are available/known public exploitation
- Vendor: Siemens
- Equipment: SINEC INS
- Vulnerabilities: Improper Authentication, Out-of-bounds Write, Ineffici
Microsoft
Excessive time spent checking invalid RSA public keys
vendor_msrc·2024-04-09·CVSS 5.9
CVE-2023-6237 [MEDIUM] CWE-606 Excessive time spent checking invalid RSA public keys
Excessive time spent checking invalid RSA public keys
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
openssl: openssl
Customer Action Required: Yes
Remediation: CBL-Mariner Releases
Reference: https://lea
Ubuntu
OpenSSL vulnerabilities
vendor_ubuntu·2024-02-05·CVSS 5.3
CVE-2023-6237 [MEDIUM] OpenSSL vulnerabilities
Title: OpenSSL vulnerabilities
Summary: Several security issues were fixed in OpenSSL.
David Benjamin discovered that OpenSSL incorrectly handled excessively long
X9.42 DH keys. A remote attacker could possibly use this issue to cause
OpenSSL to consume resources, leading to a denial of service.
(CVE-2023-5678)
Sverker Eriksson discovered that OpenSSL incorrectly handled POLY1304 MAC
on the PowerPC architecture. A remote attacker could use this issue to
cause OpenSSL to crash, resulting in a denial of service, or possibly
execute arbitrary code. This issue only affected Ubuntu 22.04 LTS and
Ubuntu 23.04. (CVE-2023-6129)
It was discovered that OpenSSL incorrectly handled excessively long RSA
public keys. A remote attacker could possibly use this issue to cause
OpenSSL to consume resourc
Red Hat
openssl: Excessive time spent checking invalid RSA public keys
vendor_redhat·2024-01-15·CVSS 5.9
CVE-2023-6237 [MEDIUM] CWE-400 openssl: Excessive time spent checking invalid RSA public keys
openssl: Excessive time spent checking invalid RSA public keys
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
o
Debian
CVE-2023-6237: openssl - Issue summary: Checking excessively long invalid RSA public keys may take a long...
vendor_debian·2023·CVSS 5.9
CVE-2023-6237 [MEDIUM] CVE-2023-6237: openssl - Issue summary: Checking excessively long invalid RSA public keys may take a long...
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
No detection rules found.
No public exploits indexed.
https://github.com/openssl/openssl/commit/0b0f7abfb37350794a4b8960fafc292cd5d1b84dhttps://github.com/openssl/openssl/commit/18c02492138d1eb8b6548cb26e7b625fb2414a2ahttps://github.com/openssl/openssl/commit/a830f551557d3d66a84bbb18a5b889c640c36294https://www.openssl.org/news/secadv/20240115.txthttp://www.openwall.com/lists/oss-security/2024/03/11/1https://github.com/openssl/openssl/commit/0b0f7abfb37350794a4b8960fafc292cd5d1b84dhttps://github.com/openssl/openssl/commit/18c02492138d1eb8b6548cb26e7b625fb2414a2ahttps://github.com/openssl/openssl/commit/a830f551557d3d66a84bbb18a5b889c640c36294https://security.netapp.com/advisory/ntap-20240531-0007/https://www.openssl.org/news/secadv/20240115.txthttps://cert-portal.siemens.com/productcert/html/ssa-265688.htmlhttps://cert-portal.siemens.com/productcert/html/ssa-331112.htmlhttps://cert-portal.siemens.com/productcert/html/ssa-769027.htmlhttps://cert-portal.siemens.com/productcert/html/ssa-915275.html
2024-04-25
Published