{"containers":{"cna":{"affected":[{"collectionURL":"https://repo.hex.pm","cpes":["cpe:2.3:a:slab:safeurl:*:*:*:*:*:*:*:*"],"defaultStatus":"unaffected","modules":["'Elixir.SafeURL'","'Elixir.SafeURL.HTTPoison'","'Elixir.SafeURL.TeslaMiddleware'"],"packageName":"safeurl","packageURL":"pkg:hex/safeurl","product":"safeurl","programFiles":["lib/safeurl/safeurl.ex","lib/safeurl/httpoison.ex","lib/safeurl/tesla_middleware.ex"],"programRoutines":[{"name":"'Elixir.SafeURL':validate/2"},{"name":"'Elixir.SafeURL.HTTPoison':get/3"},{"name":"'Elixir.SafeURL.TeslaMiddleware':call/3"}],"repo":"https://github.com/slab/safeurl-elixir","vendor":"Slab","versions":[{"lessThan":"*","status":"affected","version":"0.1.0","versionType":"semver"}]},{"collectionURL":"https://github.com","cpes":["cpe:2.3:a:slab:safeurl:*:*:*:*:*:*:*:*"],"defaultStatus":"unaffected","modules":["'Elixir.SafeURL'","'Elixir.SafeURL.HTTPoison'","'Elixir.SafeURL.TeslaMiddleware'"],"packageName":"slab/safeurl-elixir","packageURL":"pkg:github/slab/safeurl-elixir","product":"safeurl","programFiles":["lib/safeurl/safeurl.ex","lib/safeurl/httpoison.ex","lib/safeurl/tesla_middleware.ex"],"programRoutines":[{"name":"'Elixir.SafeURL':validate/2"},{"name":"'Elixir.SafeURL.HTTPoison':get/3"},{"name":"'Elixir.SafeURL.TeslaMiddleware':call/3"}],"repo":"https://github.com/slab/safeurl-elixir","vendor":"Slab","versions":[{"lessThan":"*","status":"affected","version":"feabbd0a13f83028ab24b71710526e9da9841f70","versionType":"git"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:a:slab:safeurl:*:*:*:*:*:*:*:*","versionStartIncluding":"0.1.0","vulnerable":true}],"negate":false,"operator":"OR"}],"operator":"AND"}],"credits":[{"lang":"en","type":"reporter","value":"Jonatan Männchen / EEF"},{"lang":"en","type":"coordinator","value":"Jonatan Männchen / EEF"}],"descriptions":[{"lang":"en","supportingMedia":[{"base64":false,"type":"text/html","value":"<p>Time-of-check Time-of-use (TOCTOU) Race Condition in Slab safeurl allows an attacker who controls a hostname's DNS responses to reach internal network destinations that validation rejected.</p>\n<p>Validation returns a verdict and not the address it approved, so the HTTP clients the library ships receive the original hostname and resolve it a second time when the request is made. An attacker who controls the authoritative DNS for a name can answer the first lookup with a permitted address and the second with a blocked one, and the request then reaches a destination validation never approved. The same window opens without an attacker whenever a name legitimately resolves to different addresses across lookups, such as short record lifetimes or rotation between several addresses.</p>\n<p>This issue affects safeurl: from 0.1.0 onward.</p>"},{"base64":false,"type":"text/markdown","value":"Time-of-check Time-of-use (TOCTOU) Race Condition in Slab safeurl allows an attacker who controls a hostname's DNS responses to reach internal network destinations that validation rejected.\n\nValidation returns a verdict and not the address it approved, so the HTTP clients the library ships receive the original hostname and resolve it a second time when the request is made. An attacker who controls the authoritative DNS for a name can answer the first lookup with a permitted address and the second with a blocked one, and the request then reaches a destination validation never approved. The same window opens without an attacker whenever a name legitimately resolves to different addresses across lookups, such as short record lifetimes or rotation between several addresses.\n\nThis issue affects safeurl: from 0.1.0 onward."}],"value":"Time-of-check Time-of-use (TOCTOU) Race Condition in Slab safeurl allows an attacker who controls a hostname's DNS responses to reach internal network destinations that validation rejected.\n\nValidation returns a verdict and not the address it approved, so the HTTP clients the library ships receive the original hostname and resolve it a second time when the request is made. An attacker who controls the authoritative DNS for a name can answer the first lookup with a permitted address and the second with a blocked one, and the request then reaches a destination validation never approved. The same window opens without an attacker whenever a name legitimately resolves to different addresses across lookups, such as short record lifetimes or rotation between several addresses.\n\nThis issue affects safeurl: from 0.1.0 onward."}],"impacts":[{"capecId":"CAPEC-664","descriptions":[{"lang":"en","value":"CAPEC-664 Server Side Request Forgery"}]}],"metrics":[{"cvssV4_0":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"HIGH","attackRequirements":"PRESENT","attackVector":"NETWORK","baseScore":9,"baseSeverity":"CRITICAL","privilegesRequired":"NONE","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"NONE","subConfidentialityImpact":"HIGH","subIntegrityImpact":"LOW","userInteraction":"NONE","valueDensity":"NOT_DEFINED","vectorString":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N","version":"4.0","vulnAvailabilityImpact":"NONE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpact":"LOW","vulnerabilityResponseEffort":"NOT_DEFINED"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-367","description":"CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-09-15T15:37:49.948Z","orgId":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db","shortName":"EEF"},"references":[{"name":"EEF CNA record for CVE-2026-77972","tags":["related","third-party-advisory"],"url":"https://cna.erlef.org/cves/CVE-2026-77972.html"},{"name":"OSV record EEF-CVE-2026-77972","tags":["related"],"url":"https://osv.dev/vulnerability/EEF-CVE-2026-77972"},{"name":"Introducing commit feabbd0 in slab/safeurl-elixir","tags":["related"],"url":"https://github.com/slab/safeurl-elixir/commit/feabbd0a13f83028ab24b71710526e9da9841f70"}],"source":{"discovery":"EXTERNAL"},"title":"safeurl validated address is not bound to the request, allowing DNS rebinding"}},"cveMetadata":{"assignerOrgId":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db","assignerShortName":"EEF","cveId":"CVE-2026-77972","datePublished":"2026-09-15T15:37:49.948Z","dateReserved":"2026-08-24T15:45:02.127Z","dateUpdated":"2026-09-15T15:37:49.948Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"}