{"answers":{"affected":"3 open source packages ship an affected version, including github.com/gomarkdown/markdown. It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40890 exists.","fix":"Upgrade github.com/gomarkdown/markdown to 0.0.0-20260411013819-759bbc3e3207 or later.","what":"CVE-2026-40890 is a high-severity denial of service vulnerability in gomarkdown markdown, published on 21 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-40890 and fix it if it is affected.\n\nWhat it is: CVE-2026-40890 is a high-severity denial of service vulnerability in gomarkdown markdown, published on 21 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-40890 exists.\n\nAffected packages and fixed versions:\n- github.com/gomarkdown/markdown (Go): affected all versions; fixed in 0.0.0-20260411013819-759bbc3e3207\n- github.com/gomarkdown/markdown (Go): affected all versions; fixed in 0.0.0-20260411013819-759bbc3e3207\n- github.com/gomarkdown/markdown (Go): affected all versions; fixed in 0.0.0-20260411013819-759bbc3e3207\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-40890/ (Markdown: https://insights.sbomify.com/CVE-2026-40890/index.md)","id":"CVE-2026-40890","markdown":"https://insights.sbomify.com/CVE-2026-40890/index.md","name":"CVE-2026-40890","record":{"aliases":["CLEANSTART-2026-FB77791","CLEANSTART-2026-GL95997","DEBIAN-CVE-2026-40890","GHSA-77fj-vx54-gvh7","GO-2026-5208","MINI-6mmg-2qhp-9px8","MINI-83gq-c8gm-78mx","MINI-83qg-8rhq-fxqj","MINI-q92v-4qmm-mh44","MINI-rfhw-5qg9-25rp","MINI-v6jw-mj8m-3q9x","UBUNTU-CVE-2026-40890"],"analysis":{"component_type":"library","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Go Markdown library","requires_auth":"none","summary":"A malformed Markdown input can cause an out-of-bounds read or panic in the SmartypantsRenderer, leading to a denial of service.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"markdown","vendor":"gomarkdown"}],"cvss":{"score":7.5,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-125","name":"Out-of-bounds Read"}],"description":"The package `github.com/gomarkdown/markdown` is a Go library for parsing Markdown text and rendering as HTML. Processing a malformed input containing a \u003c character that is not followed by a \u003e character anywhere in the remaining text with a SmartypantsRenderer will lead to Out of Bounds read or a panic. This vulnerability is fixed with commit 759bbc3e32073c3bc4e25969c132fc520eda2778.","ecosystems":["Go"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"github.com/gomarkdown/markdown: Out-of-bounds Read in SmartypantsRenderer","id":"CVE-2026-40890","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Go","product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":3,"n_references":2,"next":{"headline":"OpenTelemetry dotnet: Unbounded `grpc-status-details-bin` parsing in OTLP/gRPC retry handling","id":"CVE-2026-40891"},"packages":[{"ecosystem":"Go","fixed":["0.0.0-20260411013819-759bbc3e3207"],"introduced":["0"],"last_affected":[],"package":"github.com/gomarkdown/markdown","purl":null,"source":"GHSA-77fj-vx54-gvh7"},{"ecosystem":"Go","fixed":["0.0.0-20260411013819-759bbc3e3207"],"introduced":["0"],"last_affected":[],"package":"github.com/gomarkdown/markdown","purl":"pkg:golang/github.com/gomarkdown/markdown","source":"GHSA-77fj-vx54-gvh7"},{"ecosystem":"Go","fixed":["0.0.0-20260411013819-759bbc3e3207"],"introduced":["0"],"last_affected":[],"package":"github.com/gomarkdown/markdown","purl":"pkg:golang/github.com/gomarkdown/markdown","source":"GO-2026-5208"}],"prev":{"headline":"Frappe HR has Improper Access Control on Files","id":"CVE-2026-40889"},"products":["markdown"],"published":"2026-04-21","related":[{"cvss_score":7.5,"headline":"github.com/gomarkdown/markdown Out-of-bounds Read while parsing citations","id":"CVE-2023-42821","kev_date_added":null,"published":"2023-09-22"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"Go Vulnerability Database","prefix":"GO"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"yes","exploitation":"poc","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-04-21","vendors":["gomarkdown"]},"summary":"A malformed Markdown input can cause an out-of-bounds read or panic in the SmartypantsRenderer, leading to a denial of service.","url":"https://insights.sbomify.com/CVE-2026-40890/"}