Security readout for executives and security teams
Plain-English summary
This is a legacy HHVM issue where one mcrypt function accepted the wrong kind of input. The public record identifies affected HHVM version ranges but does not provide a CVSS score, CWE, or concrete business impact. Treat it as an inventory and legacy-platform cleanup item unless HHVM is still running in production.
Executive priority
Moderate operational priority if HHVM is still present; low priority if HHVM has been fully retired. The main business risk is untracked legacy runtime exposure with unclear impact.
Technical view
CVE-2016-1000005 is a type confusion flaw in HHVM's mcrypt_get_block_size handling. The module parameter was not enforced as a string, so other data types could be passed. Affected ranges are HHVM before 3.9.5, 3.10.0 through 3.12.3, and 3.13.0 through 3.14.1.
Likely exposure
Exposure is most likely in legacy PHP/HHVM services using affected HHVM releases, especially code paths invoking mcrypt_get_block_size. The source bundle does not identify affected downstream products or CPEs.
Exploitation context
The source bundle does not show known active exploitation, and the CVE is not marked KEV. Public details are limited to type confusion and affected HHVM versions; exploitability and impact are not established in the provided sources.
Researcher notes
Evidence is thin: no CVSS, CWE, CPE, exploit status, or detailed impact is provided. Analysis should stay anchored to HHVM version exposure and the specific type-checking defect described by the CVE and vendor references.
Mitigation direction
- Inventory HHVM deployments and record exact runtime versions.
- Upgrade HHVM to a version outside the affected ranges, following vendor guidance.
- Prioritize internet-facing or high-trust services still using affected HHVM versions.
- Review application dependency plans for removing obsolete mcrypt usage.
Validation and detection
- Check runtime version banners, package metadata, or deployment manifests for affected HHVM ranges.
- Search application code for mcrypt_get_block_size usage.
- Confirm no production service still runs affected HHVM versions.
- Document any compensating controls where immediate upgrade is not possible.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
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CVE-2016-1000005 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/facebook/hhvm/commit/39e7e177473350b3a5c34e8824af3b98e25efa89CVE reference · x_refsource_CONFIRM
- https://www.facebook.com/security/advisories/cve-2016-1000005CVE reference · x_refsource_CONFIRM
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.