CVE-2026-74871
openssl_encrypt before 1.4.6 KDF Bypass via Sequential-XOR
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.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- 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
openssl_encrypt before 1.4.6 KDF Bypass via Sequential-XOR
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.
- Record
CVE-2026-74871- CVSS 4.0
- 6.9 Medium
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 - CVSS 3.1
- 6.2 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-916
- Updated
- 2026-11-02
EUVDEUVD-2026-60090
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.
- Record
EUVD-2026-60090- CVSS 4.0
- 6.9 Medium
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 - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-pj8r-rv9w-cfg8
openssl_encrypt versions before 1.4.6 contain a key derivation flaw in sequential XOR composition...
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.
- Record
GHSA-pj8r-rv9w-cfg8- CVSS 4.0
- 6.9 Medium
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 - CVSS 3.1
- 6.2 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-916
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-74871- CVSS 4.0
- 6.9 Medium
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 - CVSS 3.1
- 6.2 Medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-916
- Updated
- 2026-11-02
OSV
openssl_encrypt before 1.4.6 KDF Bypass via Sequential-XOR
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.
- Record
CVE-2026-74871- CVSS 4.0
- 6.9 Medium
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 - Weakness
- CWE-916
- Updated
- 2026-11-02
OSVPYSEC-2026-3976
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.
- Record
PYSEC-2026-3976- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
openssl-encryptPyPI |
before 1.4.6, plus listed versions 0.2.20.2.30.2.40.2.50.2.6 Show 45 moreShow less0.3.00.3.10.3.20.3.30.4.00.4.10.4.20.4.30.4.40.5.00.5.10.5.30.6.0rc10.7.0rc20.7.10.7.20.8.00.8.10.8.20.9.21.0.01.0.11.0.21.0.31.1.01.2.01.2.11.3.01.3.11.3.21.3.31.3.41.3.51.4.01.4.0b31.4.0b41.4.0b51.4.0b61.4.0b71.4.0b81.4.11.4.1rc21.4.21.4.41.4.5 |
1.4.6 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-74871 is a medium vulnerability (CVSS 6.9) in Jahlives Openssl Encrypt, published August 17, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.11%, the 1st percentile. Fixed in openssl-encrypt 1.4.6.
References
github.com/jahlives/openssl_encrypt/security/advisories/GHSA-vxf9-vwp6-2w43
vulncheck.com/advisories/openssl-encrypt-before-kdf-bypass-via-sequential-xor
nvd.nist.gov/vuln/detail/CVE-2026-74871