CVE-2026-74899 json
openssl_encrypt before 1.4.0 Sandbox Escape via Type Hierarchy
published 2026-08-17 2 mo ago modified 2026-10-01 39 d ago also PYSEC-2026-3727 , EUVD-2026-60116
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.8%
- EPSS 0.8% chance of exploitation in 30 days, percentile 55%
- public exploits
- 0
- none known
Summary
openssl_encrypt versions before 1.4.0 contain a sandbox escape vulnerability in IsolatedPluginExecutor that exposes Python type objects in restricted exec() builtins. Attackers can traverse the Python class hierarchy via __class__.__mro__.__subclasses__() to access system functions and execute arbitrary OS commands.
Patch / fix
- pypi openssl-encrypt 1.4.0
- jahlives openssl_encrypt 1.4.0
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- total
- Assessed
- 2 mo ago
Exploit prediction
0.75% chance of exploitation in the next 30 days, higher than 55% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/siyuan-note/siyuan/security/advisories/GHSA-43jx-gxq4-jpjc referenced PoC, tagged "exploit" by a source, unverified
- github.com https://github.com/jahlives/openssl_encrypt/security/advisories/GHSA-m25m-ggxg-239c referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 9.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| CNA | 4.0 | 9.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | openssl-encrypt | <1.4.0 |
1.4.0 |
Affected products
- jahlives openssl_encrypt
Classification
- Weakness
-
- CWE-95 Improper Neutralization of Directives in Dynamically Evaluated Code
References
-
github.com
/siyuan-note/siyuan/security/advisories/GHSA-43jx-gxq4-jpjc
exploit, not-applicable, advisory
-
github.com
/jahlives/openssl_encrypt/security/advisories/GHSA-m25m-ggxg-239c
vendor-advisory, exploit, mitigation, evidence
-
vulncheck.com
/advisories/openssl-encrypt-before-sandbox-escape-via-type-hierarchy
third-party-advisory, advisory
Sources
- CVE List CVE-2026-74899
- NVD CVE-2026-74899
- OSV PYSEC-2026-3727
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.