CVE-2023-50781
M2crypto: bleichenbacher timing attacks in the rsa decryption api - incomplete fix for cve-2020-25657
A flaw was found in m2crypto. This issue may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
M2crypto: bleichenbacher timing attacks in the rsa decryption api - incomplete fix for cve-2020-25657
A flaw was found in m2crypto. This issue may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.
- Record
CVE-2023-50781- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-203
- Updated
- 2026-11-02
EUVDEUVD-2024-0587
A flaw was found in m2crypto. This issue may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.
- Record
EUVD-2024-0587- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-944j-8ch6-rf6x
m2crypto Bleichenbacher timing attack - incomplete fix for CVE-2020-25657
A flaw was found in m2crypto. This issue may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.
- Record
GHSA-944j-8ch6-rf6x- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-203, CWE-208, CWE-385
- Updated
- 2026-11-02
NVD
A flaw was found in m2crypto. This issue may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.
- Record
CVE-2023-50781- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-203
- Updated
- 2026-11-02
OSVAZL-101841
CVE-2023-50781 affecting package m2crypto 0.38.0-5
A flaw was found in m2crypto. This issue may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.
- Record
AZL-101841- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-05
OSV
A flaw was found in m2crypto. This issue may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.
- Record
CVE-2023-50781- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
Show 4 moreShow less
OSVDEBIAN-CVE-2023-50781
A flaw was found in m2crypto. This issue may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.
- Record
DEBIAN-CVE-2023-50781- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVGHSA-944j-8ch6-rf6x
m2crypto Bleichenbacher timing attack - incomplete fix for CVE-2020-25657
A flaw was found in m2crypto. This issue may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.
- Record
GHSA-944j-8ch6-rf6x- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-203, CWE-208, CWE-385
- Updated
- 2026-11-02
OSVPYSEC-2026-1595
m2crypto Bleichenbacher timing attack - incomplete fix for CVE-2020-25657
A flaw was found in m2crypto. This issue may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.
- Record
PYSEC-2026-1595- CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVUBUNTU-CVE-2023-50781
A flaw was found in m2crypto. This issue may allow a remote attacker to decrypt captured messages in TLS servers that use RSA key exchanges, which may lead to exposure of confidential or sensitive data.
- Record
UBUNTU-CVE-2023-50781- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
Affected products
- m2crypto project m2crypto
- red hat enterprise linux 6
- red hat enterprise linux 7
- red hat enterprise linux 8
- red hat enterprise linux 9
- red hat update infrastructure 4 for cloud providers
- red hat virtualization 4
- redhat enterprise linux
- redhat update infrastructure
- siemens simatic s7-1500 tm mfp - gnu/linux subsystem
Affected packages
| Package | Affected | Fixed |
|---|---|---|
m2cryptoPyPI |
through 0.40.1 | None known |
m2cryptoAzure Linux:3 |
through 0.38.0-5 | None known |
m2cryptoDebian:12 |
All versions, plus listed versions 0.38.0-40.38.0-4.10.40.1-10.40.1-20.40.1-3 Show 12 moreShow less0.40.1-40.41.0+ds-10.41.0+ds-20.41.0+ds-30.41.0-10.42.0-10.42.0-20.42.0-2.10.42.0-30.46.2-10.46.2-20.46.2-3 |
None known |
m2cryptoDebian:13 |
before 0.40.1-3 | 0.40.1-3 |
m2cryptoPyPI |
through 0.40.1, plus listed versions 0.110.130.150.160.17 Show 42 moreShow less0.180.18.10.18.20.190.19.10.200.20.10.20.20.20beta10.210.21.10.22.30.22.40.22.50.23.00.24.00.25.00.25.10.26.00.26.20.26.30.26.40.27.00.28.00.28.10.28.20.29.00.30.00.30.10.31.00.32.00.33.00.34.00.35.00.35.10.35.20.36.00.37.00.37.10.38.00.39.00.40.0 |
None known |
m2cryptoUbuntu:14.04:LTS |
All versions, plus listed versions 0.21.1-3ubuntu30.21.1-3ubuntu40.21.1-3ubuntu5 |
None known |
m2cryptoUbuntu:16.04:LTS |
All versions, plus listed versions 0.21.1-3ubuntu50.22.6~rc4-1ubuntu1 |
None known |
m2cryptoUbuntu:18.04:LTS |
All versions, plus listed versions 0.24.0-20.27.0-20.27.0-40.27.0-4build10.27.0-5 |
None known |
m2cryptoUbuntu:20.04:LTS |
All versions, plus listed versions 0.31.0-60.31.0-6build10.31.0-70.31.0-80.31.0-9ubuntu1 |
None known |
m2cryptoUbuntu:22.04:LTS |
All versions, plus listed versions 0.37.1-1ubuntu30.37.1-1ubuntu40.38.0-1ubuntu30.38.0-1ubuntu5 |
None known |
m2cryptoUbuntu:24.04:LTS |
All versions, plus listed versions 0.38.0-4build10.38.0-4.10.40.1-0ubuntu10.40.1-10.40.1-2build10.40.1-2build20.40.1-2ubuntu1 |
None known |
m2cryptoUbuntu:25.10 |
All versions, plus listed versions 0.42.0-2.1build10.42.0-3 |
None known |
m2cryptoUbuntu:26.04:LTS |
All versions, plus listed versions 0.42.0-30.46.2-20.46.2-30.46.2-3build1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | OSV | |
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2023-50781 is a high vulnerability (CVSS 7.5) in M2crypto Project M2crypto, published February 5, 2024. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.12%, the 66th percentile. Fixed in m2crypto 0.40.1-3.