Security readout for executives and security teams
Plain-English summary
This is a denial-of-service issue in certain InspIRCd IRC server deployments. A connected user can remotely crash the server only when vulnerable InspIRCd versions use the mysql module with specific SQL authentication/operator modules and a newer MariaDB C connector.
Executive priority
Treat this as a service-availability risk, not a confirmed breach indicator. Remediate promptly on public IRC servers because a connected user may cause downtime, but scope is narrower than a general remote code execution flaw.
Technical view
InspIRCd 2 before 2.0.28 and 3 before 3.3.0 have a NULL pointer dereference in the mysql module when built against mariadb-connector-c 3.0.5 or newer. Exposure requires sqlauth or sqloper to be combined with that mysql module.
Likely exposure
Likely exposure is limited to internet- or network-reachable InspIRCd servers running the affected versions with mysql plus sqlauth or sqloper enabled, built against mariadb-connector-c 3.0.5 or newer.
Exploitation context
The CVE description states any user able to connect to the server can remotely crash it. The provided sources do not show active exploitation, KEV listing, exploit availability, or data compromise.
Researcher notes
The affected condition is configuration-specific: vulnerable InspIRCd version, mysql module, mariadb-connector-c 3.0.5 or newer, and sqlauth or sqloper. Sources identify NULL pointer dereference and remote crash impact, but provide no CVSS, CWE, or active exploitation evidence.
Mitigation direction
- Upgrade InspIRCd 2.x to 2.0.28 or later.
- Upgrade InspIRCd 3.x to 3.3.0 or later.
- Apply Debian DSA-4764 or DLA 2375-1 packages where applicable.
- Review the InspIRCd advisory before changing module configuration.
- Prioritize exposed IRC servers that allow broad user connections.
Validation and detection
- Inventory InspIRCd server versions across production and staging.
- Check whether mysql, sqlauth, or sqloper modules are enabled.
- Confirm mariadb-connector-c build or package version.
- Verify Debian hosts have the referenced security updates installed.
- Review service monitoring for unexplained InspIRCd crashes.
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
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CVE-2019-20917 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://docs.inspircd.org/security/2019-02/CVE reference · x_refsource_MISC
- https://github.com/inspircd/inspircd/commit/2cc35d8625b7ea5cbd1d1ebb116aff86c5280162CVE reference · x_refsource_MISC
- https://github.com/inspircd/inspircd/commit/8745660fcdac7c1b80c94cfc0ff60928cd4dd4b7CVE reference · x_refsource_MISC
- DSA-4764CVE reference · vendor-advisory, x_refsource_DEBIAN
- [debian-lts-announce] 20200920 [SECURITY] [DLA 2375-1] inspircd security updateCVE reference · mailing-list, x_refsource_MLIST
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.