CVE-2026-74871 json
openssl_encrypt before 1.4.6 KDF Bypass via Sequential-XOR
published 2026-08-17 2 mo ago modified 2026-10-01 38 d ago also GHSA-vxf9-vwp6-2w43 , PYSEC-2026-3976 , EUVD-2026-60090
- cvss
- 6.2
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.1%
- EPSS 0.1% chance of exploitation in 30 days, percentile 1%
- public exploits
- 0
- none known
Summary
openssl_encrypt versions before 1.4.6 contain a key derivation flaw in sequential XOR composition mode where the last stage cancels out during key generation. When configured with a single KDF and no prior hashing stage, attackers can bypass memory-hard key derivation and perform offline password cracking at SHA-256 speed instead of the configured KDF cost.
Patch / fix
- pypi openssl-encrypt 1.4.6
- jahlives openssl_encrypt 1.4.6
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2 mo ago
Exploit prediction
0.11% chance of exploitation in the next 30 days, higher than 1% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 6.9 | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N |
| CNA | 3.1 | 6.2 | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| CNA | 4.0 | 6.9 | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/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 |
| NVD | 3.1 | 5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N |
| OSV | 3.1 | 5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | openssl-encrypt | <1.4.6 |
1.4.6 |
Affected products
- jahlives openssl_encrypt
Classification
- Weakness
-
- CWE-916 Use of Password Hash With Insufficient Computational Effort
References
-
github.com
/jahlives/openssl_encrypt/security/advisories/GHSA-vxf9-vwp6-2w43
vendor-advisory, mitigation, advisory
-
vulncheck.com
/advisories/openssl-encrypt-before-kdf-bypass-via-sequential-xor
third-party-advisory, advisory
Sources
- CVE List CVE-2026-74871
- NVD CVE-2026-74871
- OSV PYSEC-2026-3976
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.