Evidence used
- No CISA KEV confirmation is currently recorded.
- EPSS is 0.27% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2026
CVE-2026-94423High confidence
Net::LibSSH versions before 0.004 for Perl authenticate to an unverified server because connect never checks the host key against known_hosts
Unknown · Unknown
…UnscoredAssess manually
Needs assessment
Patch availableNo CVSS base score is available from the CNA, CISA ADP or NIST. Absence of a score is not evidence of low risk; review the vendor advisory, affected exposure and exploit evidence.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityUnscored→Operational priority:Needs assessment, manual assessment needed.unscored
Compensating controls
- Validate the affected product branch and deploy the verified fixed release.
- Restrict local access and enforce least privilege on affected hosts.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs Unknown Unknown and falls inside the recorded affected range.
- Verify the installed build against the product-specific fixed version after deployment.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
No CVSS base score is available from the CNA, CISA ADP or NIST. Absence of a score is not evidence of low risk; review the vendor advisory, affected exposure and exploit evidence.
Patch available01
What, why and how
Net::LibSSH versions before 0.004 for Perl authenticate to an unverified server because connect never checks the host key against known_hosts. connect reports success as soon as ssh_connect returns SSH_OK. libssh leaves the known-hosts check to the application, and this binding never makes it, so the strict_hostkeycheck and knownhosts options are set on the session and then decide nothing. Password, agent and public-key authentication, channel and SFTP operations all run on a session whose peer was never identified, so an attacker who can redirect the connection receives the password when password authentication is used, and commands and data sent over the session.
What
Net::LibSSH versions before 0.004 for Perl authenticate to an unverified server because connect never checks the host key against known_hosts. connect reports success as soon as ssh_connect returns SSH_OK. libssh leaves the known-hosts check to the application, and this binding never makes it, so the strict_hostkeycheck and knownhosts options are set on the session and then decide nothing. Password, agent and public-key authentication, channel and SFTP operations all run on a session whose peer was never identified, so an attacker who can redirect the connection receives the password when password authentication is used, and commands and data sent over the session.
Why
The product performs a key exchange with an actor without verifying the identity of that actor.
How
An attacker operating through the affected interface may attempt exploitation when the stated preconditions are met. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
Net::LibSSH versions before 0.004 for Perl authenticate to an unverified server because connect never checks the host key against known_hosts. connect reports success as soon as ssh_connect returns SSH_OK. libssh leaves the known-hosts check to the application, and this binding never makes it, so the strict_hostkeycheck and knownhosts options are set on the session and then decide nothing. Password, agent and public-key authentication, channel and SFTP operations all run on a session whose peer was never identified, so an attacker who can redirect the connection receives the password when password authentication is used, and commands and data sent over the session.
Why
The product performs a key exchange with an actor without verifying the identity of that actor.
How
An attacker operating through the affected interface may attempt exploitation when the stated preconditions are met. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
- Likely attack path
- the affected interface → Key Exchange without Entity Authentication → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Unspecified
- Privileges required
- Not stated in the selected CVSS metric
- User interaction
- Not stated in the selected CVSS metric
- Attack complexity
- Not stated in the selected CVSS metric
- Security boundary
- Not stated in the selected CVSS metric
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-322 ↗
CWE-322: Key Exchange without Entity Authentication. The product performs a key exchange with an actor without verifying the identity of that actor.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. Not available from the selected scoring authority.- Post-exploitation / living off the land
- No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
03
Patch and workaround
Operational remediation based on structured source evidence.
- Status
?
Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change. - Patch available
- Affected
- < 0.004
- Action
- Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
- Workaround
- No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04
Evidence and provenance
Published 21 Oct 2026 · Last source change 22 Oct 2026, 00:16 UTC · CWE-322 · Key Exchange without Entity Authentication
CVE recordCVE.org · 5.2
CVSS sourceUnavailable
EPSS source FIRST · tracked since 2026-10-22
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2026-107577
Product sourceUnavailable
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD awaiting enrichment
Missing structured fields: CVSS base score, affected product. Missing data is not evidence of low risk; review the primary advisory.
Material change intelligence
View recent updates ↗What changed after publication
- ENISA EUVD mappingEUVD-2026-107577 was added to the official ENISA EUVD mapping for this CVE.ENISA EUVD ↗
- Before
- not recorded
- After
- {"euvdId":"EUVD-2026-107577"}
- Vendor guidanceAuthoritative vendor guidance changed: added remediation: metacpan.org/changes; removed patch: github.com/29f509aacddb4b282ac9eb716d5ab326686d09a4.patch; removed remediation: github.com/29f509aacddb4b282ac9eb716d5ab326686d09a4.patch.CVE.org ↗
- Before
- patch: github.com/29f509aacddb4b282ac9eb716d5ab326686d09a4.patch · remediation: github.com/29f509aacddb4b282ac9eb716d5ab326686d09a4.patch
- After
- remediation: metacpan.org/changes
- Catalogue recordCVE added to the BlackTree catalogue.CVE.org ↗
CVE published
Fixed release or patch reference recorded
Technical terms and abbreviations used in this report
- CVE
- Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
- CVSS
- Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
- EPSS
- Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
- CWE
- Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
- CNA
- CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
- CISA ADP
- Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
- NVD
- National Vulnerability Database: NIST's enrichment service for CVE records.
- CERT / CSIRT
- A computer security incident response team that publishes warnings or coordinates incident response.
- PoC
- Proof of concept: public material that demonstrates or helps reproduce exploitation.
- CSAF
- Common Security Advisory Framework: a machine-readable format for security advisories.
- LoTL
- Living off the land: abuse of legitimate tools or system functions during an attack.