{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-58226", "assignerOrgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "state": "PUBLISHED", "assignerShortName": "EEF", "dateReserved": "2026-06-29T18:54:08.633Z", "datePublished": "2026-07-06T09:03:47.374Z", "dateUpdated": "2026-07-06T14:04:14.632Z" }, "containers": { "cna": { "affected": [ { "collectionURL": "https://repo.hex.pm", "cpes": [ "cpe:2.3:a:elixir-mint:hpax:*:*:*:*:*:*:*:*" ], "defaultStatus": "unaffected", "modules": [ "Elixir.HPAX", "Elixir.HPAX.Types" ], "packageName": "hpax", "packageURL": "pkg:hex/hpax", "product": "hpax", "programFiles": [ "lib/hpax.ex", "lib/hpax/types.ex" ], "programRoutines": [ { "name": "'Elixir.HPAX':decode/2" }, { "name": "'Elixir.HPAX.Types':decode_integer/2" }, { "name": "'Elixir.HPAX.Types':decode_remaining_integer/3" } ], "repo": "https://github.com/elixir-mint/hpax", "vendor": "elixir-mint", "versions": [ { "lessThan": "1.0.4", "status": "affected", "version": "0.1.1", "versionType": "semver" } ] }, { "collectionURL": "https://github.com", "cpes": [ "cpe:2.3:a:elixir-mint:hpax:*:*:*:*:*:*:*:*" ], "defaultStatus": "unaffected", "modules": [ "Elixir.HPAX", "Elixir.HPAX.Types" ], "packageName": "elixir-mint/hpax", "packageURL": "pkg:github/elixir-mint/hpax", "product": "hpax", "programFiles": [ "lib/hpax.ex", "lib/hpax/types.ex" ], "programRoutines": [ { "name": "'Elixir.HPAX':decode/2" }, { "name": "'Elixir.HPAX.Types':decode_integer/2" }, { "name": "'Elixir.HPAX.Types':decode_remaining_integer/3" } ], "repo": "https://github.com/elixir-mint/hpax", "vendor": "elixir-mint", "versions": [ { "lessThan": "1ba4bb2dc91e80089cf89c73970ac3ded76f17eb", "status": "affected", "version": "56db437a7e2c515e3bdd770ac7947b02cd2390d0", "versionType": "git" } ] } ], "cpeApplicability": [ { "nodes": [ { "cpeMatch": [ { "criteria": "cpe:2.3:a:elixir-mint:hpax:*:*:*:*:*:*:*:*", "versionEndExcluding": "1.0.4", "versionStartIncluding": "0.1.1", "vulnerable": true } ], "negate": false, "operator": "AND" } ], "operator": "OR" } ], "credits": [ { "lang": "en", "type": "finder", "value": "Peter Ullrich" }, { "lang": "en", "type": "remediation developer", "value": "Andrea Leopardi" }, { "lang": "en", "type": "analyst", "value": "Jonatan Männchen / EEF" }, { "lang": "en", "type": "analyst", "value": "Eric Meadows-Jönsson" } ], "descriptions": [ { "lang": "en", "supportingMedia": [ { "base64": false, "type": "text/html", "value": "

Inefficient Algorithmic Complexity vulnerability in elixir-mint hpax allows unauthenticated denial-of-service via unbounded HPACK integer decoding.

hpax decodes HPACK variable-length integers with no upper bound on the decoded value or the number of continuation octets. 'Elixir.HPAX.Types':decode_remaining_integer/3 accumulates the integer as int + (value <<< m), shifting by 7 more bits for each continuation octet and stopping only on a terminating octet or truncated input, never because the integer grew too large. Because BEAM integers are arbitrary precision, a run of N continuation octets builds an O(N)-bit bignum and re-adds into an ever-larger bignum on each step, so the total decoding cost is superlinear (about O(N^2)). An unauthenticated attacker who can send an HTTP/2 header block to a server using this decoder (reached through the 'Elixir.HPAX':decode/2 entry point) can supply a small header block that forces a large, attacker-controlled amount of CPU (and transient memory), a denial-of-service amplification.

This issue affects hpax from 0.1.1 before 1.0.4.

" } ], "value": "Inefficient Algorithmic Complexity vulnerability in elixir-mint hpax allows unauthenticated denial-of-service via unbounded HPACK integer decoding.\n\nhpax decodes HPACK variable-length integers with no upper bound on the decoded value or the number of continuation octets. 'Elixir.HPAX.Types':decode_remaining_integer/3 accumulates the integer as int + (value <<< m), shifting by 7 more bits for each continuation octet and stopping only on a terminating octet or truncated input, never because the integer grew too large. Because BEAM integers are arbitrary precision, a run of N continuation octets builds an O(N)-bit bignum and re-adds into an ever-larger bignum on each step, so the total decoding cost is superlinear (about O(N^2)). An unauthenticated attacker who can send an HTTP/2 header block to a server using this decoder (reached through the 'Elixir.HPAX':decode/2 entry point) can supply a small header block that forces a large, attacker-controlled amount of CPU (and transient memory), a denial-of-service amplification.\n\nThis issue affects hpax from 0.1.1 before 1.0.4." } ], "impacts": [ { "capecId": "CAPEC-130", "descriptions": [ { "lang": "en", "value": "CAPEC-130 Excessive Allocation" } ] } ], "metrics": [ { "cvssV4_0": { "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "baseScore": 8.7, "baseSeverity": "HIGH", "privilegesRequired": "NONE", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE" }, "format": "CVSS", "scenarios": [ { "lang": "en", "value": "GENERAL" } ] } ], "problemTypes": [ { "descriptions": [ { "cweId": "CWE-407", "description": "CWE-407 Inefficient Algorithmic Complexity", "lang": "en", "type": "CWE" } ] } ], "providerMetadata": { "orgId": "6b3ad84c-e1a6-4bf7-a703-f496b71e49db", "shortName": "EEF", "dateUpdated": "2026-07-06T14:04:14.632Z" }, "references": [ { "tags": [ "vendor-advisory", "related" ], "url": "https://github.com/elixir-mint/hpax/security/advisories/GHSA-jj2p-32j7-whj2" }, { "tags": [ "related" ], "url": "https://cna.erlef.org/cves/CVE-2026-58226.html" }, { "tags": [ "related" ], "url": "https://osv.dev/vulnerability/EEF-CVE-2026-58226" }, { "tags": [ "patch" ], "url": "https://github.com/elixir-mint/hpax/commit/1ba4bb2dc91e80089cf89c73970ac3ded76f17eb" } ], "source": { "discovery": "EXTERNAL" }, "title": "Unauthenticated denial-of-service via unbounded HPACK integer decoding in hpax", "x_generator": { "engine": "cvelib 1.8.0" } }, "adp": [ { "references": [ { "url": "https://github.com/elixir-mint/hpax/security/advisories/GHSA-jj2p-32j7-whj2", "tags": [ "exploit" ] } ], "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2026-07-06T12:49:38.954923Z", "id": "CVE-2026-58226", "options": [ { "Exploitation": "poc" }, { "Automatable": "yes" }, { "Technical Impact": "partial" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-07-06T12:49:52.028Z" } } ] } }