M2crypto: bleichenbacher timing attacks in the rsa decryption api - incomplete fix for cve-2020-25657
Priority LOW 35CWE-203Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-203.
Summary
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.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01124 66th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | m2crypto | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 6 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 7 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 8 | — | — | Not affected | CNA |
| Red Hat | Red Hat Enterprise Linux 9 | — | — | Not affected | CNA |
| Red Hat | Red Hat Enterprise Linux 9 | — | — | Not affected | CNA |
| Red Hat | Red Hat Update Infrastructure 4 for Cloud Providers | — | — | No fix listed | CNA |
| Red Hat | Red Hat Virtualization 4 | — | — | Not affected | CNA |
| — | m2crypto (PyPI) | up to 0.40.1 | — | No fix listed | GHSA-944j-8ch6-rf6x |
- m2crypto Vendor— Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 6 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in — Not affected CNA
- Red Hat Update Infrastructure 4 for Cloud Providers VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Virtualization 4 VendorRed Hat Affected — Fixed in — Not affected CNA
- m2crypto (PyPI) Vendor— Affected up to 0.40.1 Fixed in — No fix listed GHSA-944j-8ch6-rf6x
CPE configurations NVD · 4
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* | 8.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:* | 9.0 | Vulnerable | Red Hat |
| cpe:2.3:a:redhat:update_infrastructure:4:*:*:*:*:*:*:* | 4 | Vulnerable | Red Hat |
| cpe:2.3:a:m2crypto_project:m2crypto:*:*:*:*:*:*:*:* | up to 0.40.1 | Vulnerable | M2crypto Project |
- cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Red Hat
- cpe:2.3:a:redhat:update_infrastructure:4:*:*:*:*:*:*:* Versions 4 Vulnerable ·Red Hat
- cpe:2.3:a:m2crypto_project:m2crypto:*:*:*:*:*:*:*:* Versions up to 0.40.1 Vulnerable ·M2crypto Project
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix planned: Out of support scope |
| Red Hat Update Infrastructure 4 for Cloud Providers | Affected | No fix yet |
Not affected: 3 products
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat Virtualization 4
Timeline
- 2026-10-02 Threatist record created from CVE-2023-50781
- 2026-10-03 Alias added: GHSA-944j-8ch6-rf6x
References
More Red Hat Enterprise Linux vulnerabilities
- TI-2019-08259 Underflow in PHP-FPM can lead to RCE KEVCVSS 3.1CRITICAL 9.8
- TI-2018-10530 Code injection in [UNKNOWN] RichFaces KEVCVSS 3.1CRITICAL 9.8
- TI-2014-05975 GNU Bash through 4.3 bash43-025 processes trailing strings after certain malformed… KEVCVSS 3.1CRITICAL 9.8
- TI-2014-05157 GNU Bash through 4.3 processes trailing strings after function definitions in the values… KEVCVSS 3.1CRITICAL 9.8
- TI-2025-23530 Sudo before 1.9.17p1 allows local users to obtain root access because /etc/nsswitch.conf… KEVCVSS 3.1CRITICAL 9.3
- TI-2021-17490 mod_proxy SSRF KEVCVSS 3.1CRITICAL 9.0
Sources
- CVE-2023-50781 · CVE Program
- CVE-2023-50781 · NVD
- FIRST EPSS
- GHSA-944j-8ch6-rf6x · GitHub Advisory Database · CC BY 4.0
- CVE-2023-50781 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences