CVE-2026-74890 json
openssl_encrypt before 1.4.0 HMAC Authentication Bypass via Environment Variable
published 2026-08-17 2 mo ago modified 2026-10-24 16 d ago also GHSA-rvc2-5jxq-gpcj , PYSEC-2026-3766 , EUVD-2026-60109
- cvss
- 5.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 11%
- public exploits
- 0
- none known
Summary
openssl_encrypt versions before 1.4.0 contain an authentication bypass vulnerability in CamelliaCipher that disables HMAC tag generation and verification when the PYTEST_CURRENT_TEST environment variable is set. Attackers with code execution can set this environment variable to produce unauthenticated ciphertext and bypass integrity protection on encrypted data.
Patch / fix
- pypi openssl-encrypt 1.4.0
- jahlives openssl_encrypt 1.4.0
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2 mo ago
Exploit prediction
0.21% chance of exploitation in the next 30 days, higher than 11% of all scored CVEs (FIRST EPSS, 2026-11-08).
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 | 5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N |
| 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-345 Insufficient Verification of Data Authenticity
References
-
github.com
/jahlives/openssl_encrypt/security/advisories/GHSA-rvc2-5jxq-gpcj
vendor-advisory, mitigation, advisory
-
vulncheck.com
/advisories/openssl-encrypt-before-hmac-authentication-bypass-via-environment-variable
third-party-advisory, advisory
Sources
- CVE List CVE-2026-74890
- NVD CVE-2026-74890
- OSV PYSEC-2026-3766
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