Medium

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.

Published Aug 17, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: VulnCheck

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.1% (30-day exploitation probability)+0
Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.11%

ahead of 1% of scored CVEs · Oct 15, 2026

Affects

Jahlives

Openssl Encrypt

CVSS base

5.5

Medium · 3 source(s)

Prioritization reference: 6.2 provisional

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation

None

none · proof-of-concept · active

Automatable

can an attacker script the kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

Documented mitigation — github.com (NIST National Vulnerability Database)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Jahlives Openssl Encrypt).
Apply the documented mitigations until a definitive fix is available.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Jahlives	Openssl Encrypt	< 1.4.6	Vulnerable	NIST National Vulnerability Database
Jahlives	Openssl Encrypt	< 1.4.6	Vulnerable	CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Local

Attack complexity

Low

Privileges required

Low

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
6.9	CVSS 4.0	Medium	—	—	disclosure@vulncheck.com via NIST National Vulnerability Database
6.9	CVSS 4.0	Medium	—	—	VulnCheck via CVE Program (cve.org) e CISA ADP
6.2	CVSS 3.1	Medium	2.5	3.6	disclosure@vulncheck.com via NIST National Vulnerability Database
6.2	CVSS 3.1	Medium	—	—	VulnCheck via CVE Program (cve.org) e CISA ADP
5.5	CVSS 3.1	Medium	1.8	3.6	nvd@nist.gov via NIST National Vulnerability Database

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N (score shown at the top: nvd@nist.gov)

Scoring entities (NIST, CNA, ADP) score independently; each score is shown with its origin. For prioritization we use 6.2 (disclosure@vulncheck.com via NIST National Vulnerability Database) as a conservative provisional reference — not a definitive official score.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-916

Other CVEs with this weakness →

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.

endpoint telemetry (EDR)

Timeline

What happened to this CVE, newest first.

2026
Affected products added · jahlives/openssl encrypt
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 15, 2026
Fix documented
Oct 15, 2026 · NIST National Vulnerability Database
CVSS changed · 5.5
Oct 15, 2026 · NIST National Vulnerability Database
Source status changed · → Analyzed
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Aug 17, 2026 · VulnCheck

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

2 on the record

github.com/jahlives/openssl_encrypt/security/advisories/GHSA-vxf9-vwp6-2w43
Mitigation, Vendor Advisory, vendor-advisory, NIST National Vulnerability Database
www.vulncheck.com/advisories/openssl-encrypt-before-kdf-bypass-via-sequential-xor
Third Party Advisory, third-party-advisory, NIST National Vulnerability Database

Elsewhere on this site

Jahlives
every CVE for this vendor

CWE-916
other pages naming this weakness

Related CVEs (same products)

High CVE-2026-81718 openssl_encrypt before 1.4.9 Weak Cryptographic Parameters Aug 27, 2026
Low CVE-2026-81717 openssl_encrypt before 1.4.9 Integrity Bypass via Added Files Aug 27, 2026
High CVE-2026-81719 openssl_encrypt before 1.4.9 Remote Code Execution via Plugin Aug 27, 2026
Medium CVE-2026-81720 openssl_encrypt before 1.4.9 Denial of Service via Unbounded Argon2 Aug 27, 2026
High CVE-2026-81721 openssl_encrypt before 1.4.9 Denial of Service via KDF Aug 27, 2026
Medium CVE-2026-81716 openssl_encrypt before 1.4.9 Plugin Sandbox Path Traversal Aug 27, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-74871 is "openssl_encrypt before 1.4.6 KDF Bypass via Sequential-XOR", rated Medium. It affects Openssl Encrypt (Jahlives); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.5 describes technical severity. EPSS 0.11% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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