CVE-2026-53428 (GCVE-0-2026-53428)
Vulnerability from cvelistv5 – Published: 2026-06-29 18:52 – Updated: 2026-06-30 04:38
VLAI
Title
Unbounded memory allocation in highlight_lines range expansion in mdex
Summary
Memory Allocation with Excessive Size Value vulnerability in leandrocp mdex allows an unauthenticated attacker to cause a denial of service through unbounded memory allocation.
comrak_nif::lumis_adapter::LumisAdapter::parse_highlight_lines in native/comrak_nif/src/lumis_adapter.rs eagerly expands a user-controlled inclusive line range from a fenced code block's highlight_lines decorator into a Vec<usize>, pushing one element per integer in the range with no upper bound on the range size. An attacker who can supply Markdown that an application renders with MDEx.to_html/2 (for example a comment, chat message, or wiki page) can embed a code block whose info string is rust highlight_lines="1-100000000", forcing the native adapter to allocate roughly 8 bytes per line in the range.
A payload that differs by only a few bytes can therefore allocate hundreds of megabytes, and a sufficiently large range (for example 1-2000000000) exhausts host memory and aborts the BEAM, denying service to every user of the rendering process. The per-line write loop additionally tests membership with a linear scan over the same vector, degrading rendering to a quadratic cost even for ranges that do not immediately exhaust memory.
The vulnerable native code originally shipped inside mdex (in native/comrak_nif/src/lumis_adapter.rs) and was later extracted into the separate mdex_native package (native/mdex_native_nif/src/lumis_adapter.rs), where it remains unpatched.
This issue affects mdex from 0.11.0 before 0.12.3, and mdex_native from 0.1.0 before 0.2.3.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-789 - Memory Allocation with Excessive Size Value
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/leandrocp/mdex_native/security… | vendor-advisoryrelated |
| https://cna.erlef.org/cves/CVE-2026-53428.html | related |
| https://osv.dev/vulnerability/EEF-CVE-2026-53428 | related |
| https://github.com/leandrocp/mdex_native/commit/7… | patch |
Impacted products
4 products
| Vendor | Product | Version | |
|---|---|---|---|
| leandrocp | mdex |
Affected:
0.11.0 , < 0.12.3
(semver)
cpe:2.3:a:leandrocp:mdex:*:*:*:*:*:*:*:* |
|
| leandrocp | mdex |
Affected:
a8407611715d1ead35fbcba79c72cef1b7df387b , < 6ed94d905f97af188323f042698ae841c02293b4
(git)
cpe:2.3:a:leandrocp:mdex:*:*:*:*:*:*:*:* |
|
| leandrocp | mdex_native |
Affected:
0.1.0 , < 0.2.3
(semver)
cpe:2.3:a:leandrocp:mdex_native:*:*:*:*:*:*:*:* |
|
| leandrocp | mdex_native |
Affected:
956528c5e31746253347029e810a969ab916fd27 , < 798a363b4339f6f7162ec8437c4c9f9b5ae6fbf3
(git)
cpe:2.3:a:leandrocp:mdex_native:*:*:*:*:*:*:*:* |
Credits
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An attacker who can supply Markdown that an application renders with MDEx.to_html/2 (for example a comment, chat message, or wiki page) can embed a code block whose info string is rust highlight_lines=\\\"1-100000000\\\", forcing the native adapter to allocate roughly 8 bytes per line in the range.\\n\\nA payload that differs by only a few bytes can therefore allocate hundreds of megabytes, and a sufficiently large range (for example 1-2000000000) exhausts host memory and aborts the BEAM, denying service to every user of the rendering process. The per-line write loop additionally tests membership with a linear scan over the same vector, degrading rendering to a quadratic cost even for ranges that do not immediately exhaust memory.\\n\\nThe vulnerable native code originally shipped inside mdex (in native/comrak_nif/src/lumis_adapter.rs) and was later extracted into the separate mdex_native package (native/mdex_native_nif/src/lumis_adapter.rs), where it remains unpatched.\\n\\nThis issue affects mdex from 0.11.0 before 0.12.3, and mdex_native from 0.1.0 before 0.2.3.\"}],\"affected\":[{\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\",\"affectedData\":[{\"vendor\":\"leandrocp\",\"product\":\"mdex\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://repo.hex.pm\",\"packageName\":\"mdex\",\"cpes\":[\"cpe:2.3:a:leandrocp:mdex:*:*:*:*:*:*:*:*\"],\"modules\":[\"\u0027Elixir.MDEx\u0027\",\"comrak_nif\"],\"programFiles\":[\"native/comrak_nif/src/lumis_adapter.rs\"],\"programRoutines\":[{\"name\":\"comrak_nif::lumis_adapter::LumisAdapter::parse_highlight_lines\"},{\"name\":\"\u0027Elixir.MDEx\u0027:to_html/2\"}],\"repo\":\"https://github.com/leandrocp/mdex\",\"packageURL\":\"pkg:hex/mdex\",\"versions\":[{\"version\":\"0.11.0\",\"lessThan\":\"0.12.3\",\"versionType\":\"semver\",\"status\":\"affected\"}]},{\"vendor\":\"leandrocp\",\"product\":\"mdex\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://github.com\",\"packageName\":\"leandrocp/mdex\",\"cpes\":[\"cpe:2.3:a:leandrocp:mdex:*:*:*:*:*:*:*:*\"],\"modules\":[\"\u0027Elixir.MDEx\u0027\",\"comrak_nif\"],\"programFiles\":[\"native/comrak_nif/src/lumis_adapter.rs\"],\"programRoutines\":[{\"name\":\"comrak_nif::lumis_adapter::LumisAdapter::parse_highlight_lines\"},{\"name\":\"\u0027Elixir.MDEx\u0027:to_html/2\"}],\"repo\":\"https://github.com/leandrocp/mdex\",\"packageURL\":\"pkg:github/leandrocp/mdex\",\"versions\":[{\"version\":\"a8407611715d1ead35fbcba79c72cef1b7df387b\",\"lessThan\":\"6ed94d905f97af188323f042698ae841c02293b4\",\"versionType\":\"git\",\"status\":\"affected\"}]},{\"vendor\":\"leandrocp\",\"product\":\"mdex_native\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://repo.hex.pm\",\"packageName\":\"mdex_native\",\"cpes\":[\"cpe:2.3:a:leandrocp:mdex_native:*:*:*:*:*:*:*:*\"],\"modules\":[\"\u0027Elixir.MDExNative.Comrak\u0027\",\"mdex_native_nif\"],\"programFiles\":[\"native/mdex_native_nif/src/lumis_adapter.rs\"],\"programRoutines\":[{\"name\":\"mdex_native_nif::lumis_adapter::LumisAdapter::parse_highlight_lines\"},{\"name\":\"\u0027Elixir.MDExNative.Native\u0027:document_to_html_with_options/2\"},{\"name\":\"\u0027Elixir.MDExNative.Comrak\u0027:document_to_html/2\"}],\"repo\":\"https://github.com/leandrocp/mdex_native\",\"packageURL\":\"pkg:hex/mdex_native\",\"versions\":[{\"version\":\"0.1.0\",\"lessThan\":\"0.2.3\",\"versionType\":\"semver\",\"status\":\"affected\"}]},{\"vendor\":\"leandrocp\",\"product\":\"mdex_native\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://github.com\",\"packageName\":\"leandrocp/mdex_native\",\"cpes\":[\"cpe:2.3:a:leandrocp:mdex_native:*:*:*:*:*:*:*:*\"],\"modules\":[\"\u0027Elixir.MDExNative.Comrak\u0027\",\"mdex_native_nif\"],\"programFiles\":[\"native/mdex_native_nif/src/lumis_adapter.rs\"],\"programRoutines\":[{\"name\":\"mdex_native_nif::lumis_adapter::LumisAdapter::parse_highlight_lines\"},{\"name\":\"\u0027Elixir.MDExNative.Native\u0027:document_to_html_with_options/2\"},{\"name\":\"\u0027Elixir.MDExNative.Comrak\u0027:document_to_html/2\"}],\"repo\":\"https://github.com/leandrocp/mdex_native\",\"packageURL\":\"pkg:github/leandrocp/mdex_native\",\"versions\":[{\"version\":\"956528c5e31746253347029e810a969ab916fd27\",\"lessThan\":\"798a363b4339f6f7162ec8437c4c9f9b5ae6fbf3\",\"versionType\":\"git\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"vectorString\":\"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X\",\"baseScore\":6.9,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"attackRequirements\":\"PRESENT\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"vulnConfidentialityImpact\":\"NONE\",\"vulnIntegrityImpact\":\"NONE\",\"vulnAvailabilityImpact\":\"HIGH\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"NONE\",\"subAvailabilityImpact\":\"HIGH\",\"exploitMaturity\":\"NOT_DEFINED\",\"confidentialityRequirement\":\"NOT_DEFINED\",\"integrityRequirement\":\"NOT_DEFINED\",\"availabilityRequirement\":\"NOT_DEFINED\",\"modifiedAttackVector\":\"NOT_DEFINED\",\"modifiedAttackComplexity\":\"NOT_DEFINED\",\"modifiedAttackRequirements\":\"NOT_DEFINED\",\"modifiedPrivilegesRequired\":\"NOT_DEFINED\",\"modifiedUserInteraction\":\"NOT_DEFINED\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"modifiedSubConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedSubIntegrityImpact\":\"NOT_DEFINED\",\"modifiedSubAvailabilityImpact\":\"NOT_DEFINED\",\"Safety\":\"NOT_DEFINED\",\"Automatable\":\"NOT_DEFINED\",\"Recovery\":\"NOT_DEFINED\",\"valueDensity\":\"NOT_DEFINED\",\"vulnerabilityResponseEffort\":\"NOT_DEFINED\",\"providerUrgency\":\"NOT_DEFINED\"}}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-06-29T19:17:11.005816Z\",\"id\":\"CVE-2026-53428\",\"options\":[{\"exploitation\":\"none\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-789\"}]}],\"references\":[{\"url\":\"https://cna.erlef.org/cves/CVE-2026-53428.html\",\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\"},{\"url\":\"https://github.com/leandrocp/mdex_native/commit/798a363b4339f6f7162ec8437c4c9f9b5ae6fbf3\",\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\"},{\"url\":\"https://github.com/leandrocp/mdex_native/security/advisories/GHSA-j93q-9cvj-rxfm\",\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\"},{\"url\":\"https://osv.dev/vulnerability/EEF-CVE-2026-53428\",\"source\":\"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\"}]}}",
"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-53428\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-06-29T19:17:11.005816Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-06-29T19:17:17.976Z\"}}], \"cna\": {\"title\": \"Unbounded memory allocation in highlight_lines range expansion in mdex\", \"source\": {\"discovery\": \"EXTERNAL\"}, \"credits\": [{\"lang\": \"en\", \"type\": \"finder\", \"value\": \"Peter Ullrich\"}, {\"lang\": \"en\", \"type\": \"remediation developer\", \"value\": \"Leandro Pereira\"}, {\"lang\": \"en\", \"type\": \"analyst\", \"value\": \"Jonatan M\\u00e4nnchen / EEF\"}], \"impacts\": [{\"capecId\": \"CAPEC-130\", \"descriptions\": [{\"lang\": \"en\", \"value\": \"CAPEC-130 Excessive Allocation\"}]}], \"metrics\": [{\"format\": \"CVSS\", \"cvssV4_0\": {\"version\": \"4.0\", \"baseScore\": 6.9, \"attackVector\": \"LOCAL\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"attackRequirements\": \"PRESENT\", \"privilegesRequired\": \"NONE\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"NONE\", \"subAvailabilityImpact\": \"HIGH\", \"vulnAvailabilityImpact\": \"HIGH\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"NONE\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"cpes\": [\"cpe:2.3:a:leandrocp:mdex:*:*:*:*:*:*:*:*\"], \"repo\": \"https://github.com/leandrocp/mdex\", \"vendor\": \"leandrocp\", \"modules\": [\"\u0027Elixir.MDEx\u0027\", \"comrak_nif\"], \"product\": \"mdex\", \"versions\": [{\"status\": \"affected\", \"version\": \"0.11.0\", \"lessThan\": \"0.12.3\", \"versionType\": \"semver\"}], \"packageURL\": \"pkg:hex/mdex\", \"packageName\": \"mdex\", \"programFiles\": [\"native/comrak_nif/src/lumis_adapter.rs\"], \"collectionURL\": \"https://repo.hex.pm\", \"defaultStatus\": \"unaffected\", \"programRoutines\": [{\"name\": \"comrak_nif::lumis_adapter::LumisAdapter::parse_highlight_lines\"}, {\"name\": \"\u0027Elixir.MDEx\u0027:to_html/2\"}]}, {\"cpes\": [\"cpe:2.3:a:leandrocp:mdex:*:*:*:*:*:*:*:*\"], \"repo\": \"https://github.com/leandrocp/mdex\", \"vendor\": \"leandrocp\", \"modules\": [\"\u0027Elixir.MDEx\u0027\", \"comrak_nif\"], \"product\": \"mdex\", \"versions\": [{\"status\": \"affected\", \"version\": \"a8407611715d1ead35fbcba79c72cef1b7df387b\", \"lessThan\": \"6ed94d905f97af188323f042698ae841c02293b4\", \"versionType\": \"git\"}], \"packageURL\": \"pkg:github/leandrocp/mdex\", \"packageName\": \"leandrocp/mdex\", \"programFiles\": [\"native/comrak_nif/src/lumis_adapter.rs\"], \"collectionURL\": \"https://github.com\", \"defaultStatus\": \"unaffected\", \"programRoutines\": [{\"name\": \"comrak_nif::lumis_adapter::LumisAdapter::parse_highlight_lines\"}, {\"name\": \"\u0027Elixir.MDEx\u0027:to_html/2\"}]}, {\"cpes\": [\"cpe:2.3:a:leandrocp:mdex_native:*:*:*:*:*:*:*:*\"], \"repo\": \"https://github.com/leandrocp/mdex_native\", \"vendor\": \"leandrocp\", \"modules\": [\"\u0027Elixir.MDExNative.Comrak\u0027\", \"mdex_native_nif\"], \"product\": \"mdex_native\", \"versions\": [{\"status\": \"affected\", \"version\": \"0.1.0\", \"lessThan\": \"0.2.3\", \"versionType\": \"semver\"}], \"packageURL\": \"pkg:hex/mdex_native\", \"packageName\": \"mdex_native\", \"programFiles\": [\"native/mdex_native_nif/src/lumis_adapter.rs\"], \"collectionURL\": \"https://repo.hex.pm\", \"defaultStatus\": \"unaffected\", \"programRoutines\": [{\"name\": \"mdex_native_nif::lumis_adapter::LumisAdapter::parse_highlight_lines\"}, {\"name\": \"\u0027Elixir.MDExNative.Native\u0027:document_to_html_with_options/2\"}, {\"name\": \"\u0027Elixir.MDExNative.Comrak\u0027:document_to_html/2\"}]}, {\"cpes\": [\"cpe:2.3:a:leandrocp:mdex_native:*:*:*:*:*:*:*:*\"], \"repo\": \"https://github.com/leandrocp/mdex_native\", \"vendor\": \"leandrocp\", \"modules\": [\"\u0027Elixir.MDExNative.Comrak\u0027\", \"mdex_native_nif\"], \"product\": \"mdex_native\", \"versions\": [{\"status\": \"affected\", \"version\": \"956528c5e31746253347029e810a969ab916fd27\", \"lessThan\": \"798a363b4339f6f7162ec8437c4c9f9b5ae6fbf3\", \"versionType\": \"git\"}], \"packageURL\": \"pkg:github/leandrocp/mdex_native\", \"packageName\": \"leandrocp/mdex_native\", \"programFiles\": [\"native/mdex_native_nif/src/lumis_adapter.rs\"], \"collectionURL\": \"https://github.com\", \"defaultStatus\": \"unaffected\", \"programRoutines\": [{\"name\": \"mdex_native_nif::lumis_adapter::LumisAdapter::parse_highlight_lines\"}, {\"name\": \"\u0027Elixir.MDExNative.Native\u0027:document_to_html_with_options/2\"}, {\"name\": \"\u0027Elixir.MDExNative.Comrak\u0027:document_to_html/2\"}]}], \"references\": [{\"url\": \"https://github.com/leandrocp/mdex_native/security/advisories/GHSA-j93q-9cvj-rxfm\", \"tags\": [\"vendor-advisory\", \"related\"]}, {\"url\": \"https://cna.erlef.org/cves/CVE-2026-53428.html\", \"tags\": [\"related\"]}, {\"url\": \"https://osv.dev/vulnerability/EEF-CVE-2026-53428\", \"tags\": [\"related\"]}, {\"url\": \"https://github.com/leandrocp/mdex_native/commit/798a363b4339f6f7162ec8437c4c9f9b5ae6fbf3\", \"tags\": [\"patch\"]}], \"workarounds\": [{\"lang\": \"en\", \"value\": \"Do not enable code-block decorators: leave the github_pre_lang and full_info_string render options unset, or avoid configuring an inline syntax-highlight formatter, so that highlight_lines specifications are never parsed.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"\u003cp\u003eDo not enable code-block decorators: leave the \u003ctt\u003egithub_pre_lang\u003c/tt\u003e and \u003ctt\u003efull_info_string\u003c/tt\u003e render options unset, or avoid configuring an inline syntax-highlight formatter, so that \u003ctt\u003ehighlight_lines\u003c/tt\u003e specifications are never parsed.\u003c/p\u003e\", \"base64\": false}]}], \"x_generator\": {\"engine\": \"cvelib 1.8.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"Memory Allocation with Excessive Size Value vulnerability in leandrocp mdex allows an unauthenticated attacker to cause a denial of service through unbounded memory allocation.\\n\\ncomrak_nif::lumis_adapter::LumisAdapter::parse_highlight_lines in native/comrak_nif/src/lumis_adapter.rs eagerly expands a user-controlled inclusive line range from a fenced code block\u0027s highlight_lines decorator into a Vec\u003cusize\u003e, pushing one element per integer in the range with no upper bound on the range size. An attacker who can supply Markdown that an application renders with MDEx.to_html/2 (for example a comment, chat message, or wiki page) can embed a code block whose info string is rust highlight_lines=\\\"1-100000000\\\", forcing the native adapter to allocate roughly 8 bytes per line in the range.\\n\\nA payload that differs by only a few bytes can therefore allocate hundreds of megabytes, and a sufficiently large range (for example 1-2000000000) exhausts host memory and aborts the BEAM, denying service to every user of the rendering process. The per-line write loop additionally tests membership with a linear scan over the same vector, degrading rendering to a quadratic cost even for ranges that do not immediately exhaust memory.\\n\\nThe vulnerable native code originally shipped inside mdex (in native/comrak_nif/src/lumis_adapter.rs) and was later extracted into the separate mdex_native package (native/mdex_native_nif/src/lumis_adapter.rs), where it remains unpatched.\\n\\nThis issue affects mdex from 0.11.0 before 0.12.3, and mdex_native from 0.1.0 before 0.2.3.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"Memory Allocation with Excessive Size Value vulnerability in leandrocp mdex allows an unauthenticated attacker to cause a denial of service through unbounded memory allocation.\u003cp\u003e\u003ctt\u003ecomrak_nif::lumis_adapter::LumisAdapter::parse_highlight_lines\u003c/tt\u003e in \u003ctt\u003enative/comrak_nif/src/lumis_adapter.rs\u003c/tt\u003e eagerly expands a user-controlled inclusive line range from a fenced code block\u0027s \u003ctt\u003ehighlight_lines\u003c/tt\u003e decorator into a \u003ctt\u003eVec\u0026lt;usize\u0026gt;\u003c/tt\u003e, pushing one element per integer in the range with no upper bound on the range size. An attacker who can supply Markdown that an application renders with \u003ctt\u003eMDEx.to_html/2\u003c/tt\u003e (for example a comment, chat message, or wiki page) can embed a code block whose info string is \u003ctt\u003erust highlight_lines=\\\"1-100000000\\\"\u003c/tt\u003e, forcing the native adapter to allocate roughly 8 bytes per line in the range.\u003c/p\u003e\u003cp\u003eA payload that differs by only a few bytes can therefore allocate hundreds of megabytes, and a sufficiently large range (for example \u003ctt\u003e1-2000000000\u003c/tt\u003e) exhausts host memory and aborts the BEAM, denying service to every user of the rendering process. The per-line write loop additionally tests membership with a linear scan over the same vector, degrading rendering to a quadratic cost even for ranges that do not immediately exhaust memory.\u003c/p\u003e\u003cp\u003eThe vulnerable native code originally shipped inside \u003ctt\u003emdex\u003c/tt\u003e (in \u003ctt\u003enative/comrak_nif/src/lumis_adapter.rs\u003c/tt\u003e) and was later extracted into the separate \u003ctt\u003emdex_native\u003c/tt\u003e package (\u003ctt\u003enative/mdex_native_nif/src/lumis_adapter.rs\u003c/tt\u003e), where it remains unpatched.\u003c/p\u003e\u003cp\u003eThis issue affects mdex from 0.11.0 before 0.12.3, and mdex_native from 0.1.0 before 0.2.3.\u003c/p\u003e\", \"base64\": false}]}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-789\", \"description\": \"CWE-789 Memory Allocation with Excessive Size Value\"}]}], \"configurations\": [{\"lang\": \"en\", \"value\": \"Exploitation requires the application to enable code-block decorators. Decorators are active only when the render options github_pre_lang and full_info_string are both set and an inline syntax-highlight formatter (for example {:html_inline, ...}) is configured. Applications that render Markdown with the default options do not parse highlight_lines specifications and are not affected.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"\u003cp\u003eExploitation requires the application to enable code-block decorators. Decorators are active only when the render options \u003ctt\u003egithub_pre_lang\u003c/tt\u003e and \u003ctt\u003efull_info_string\u003c/tt\u003e are both set and an inline syntax-highlight formatter (for example \u003ctt\u003e{:html_inline, ...}\u003c/tt\u003e) is configured. Applications that render Markdown with the default options do not parse \u003ctt\u003ehighlight_lines\u003c/tt\u003e specifications and are not affected.\u003c/p\u003e\", \"base64\": false}]}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:a:leandrocp:mdex:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"0.12.3\", \"versionStartIncluding\": \"0.11.0\"}], \"operator\": \"AND\"}, {\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:a:leandrocp:mdex_native:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"0.2.3\", \"versionStartIncluding\": \"0.1.0\"}], \"operator\": \"AND\"}], \"operator\": \"OR\"}], \"providerMetadata\": {\"orgId\": \"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\", \"shortName\": \"EEF\", \"dateUpdated\": \"2026-06-30T04:38:36.755Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-53428\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-06-30T04:38:36.755Z\", \"dateReserved\": \"2026-06-09T11:01:47.529Z\", \"assignerOrgId\": \"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\", \"datePublished\": \"2026-06-29T18:52:36.199Z\", \"assignerShortName\": \"EEF\"}",
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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