Security readout for executives and security teams
Plain-English summary
CVE-2018-11504 is a denial-of-service flaw in Discount 2.2.3a, a Markdown processing library/toolset. A crafted Markdown file can trigger a heap-based buffer over-read and crash processing, including mkd2html. Business impact is mainly service interruption where untrusted Markdown is converted automatically.
Executive priority
Prioritize remediation where Markdown conversion is exposed to external users or automated ingestion. For internal-only tooling, handle through normal patch cycles unless crashes affect critical publishing or documentation workflows.
Technical view
The flaw is in the islist function in markdown.c within libmarkdown.a. Public CVE text says remote attackers can cause denial of service through a crafted file, demonstrated with mkd2html. The source bundle does not provide CVSS, CWE, or comprehensive affected-version metadata beyond Discount 2.2.3a.
Likely exposure
Exposure is most likely in systems using Discount/libmarkdown or mkd2html to process user-supplied or externally sourced Markdown files, especially automated web, CI, documentation, or content pipelines.
Exploitation context
The bundle does not show CISA KEV listing or active exploitation evidence. Public sources describe a crafted-file denial-of-service condition, not code execution. Treat internet-facing or automated Markdown conversion as the higher-risk context.
Researcher notes
Evidence is limited but consistent: Discount 2.2.3a has a heap over-read denial-of-service in islist. No CVSS, CWE, exploit-in-the-wild signal, or complete product matrix is provided in the bundle.
Mitigation direction
- Apply Debian Discount security updates where applicable.
- Check upstream Discount guidance for fixed versions.
- Avoid processing untrusted Markdown with vulnerable Discount builds.
- Sandbox or isolate automated Markdown conversion jobs.
- Add crash monitoring around Markdown conversion services.
Validation and detection
- Inventory hosts and containers for Discount, libmarkdown, and mkd2html.
- Compare installed versions against Debian advisories and vendor guidance.
- Identify workflows that process user-supplied Markdown files.
- Review service logs for Markdown conversion crashes or abnormal restarts.
- Confirm updated packages are deployed across production images.
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-2018-11504 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/Orc/discount/issues/189#issuecomment-392247798CVE reference · x_refsource_MISC
- [debian-lts-announce] 20180908 [SECURITY] [DLA 1499-1] discount security updateCVE reference · mailing-list, x_refsource_MLIST
- DSA-4293CVE reference · vendor-advisory, x_refsource_DEBIAN
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.