{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-2836", "assignerOrgId": "a22f1246-ba21-4bb4-a601-ad51614c1513", "state": "PUBLISHED", "assignerShortName": "cloudflare", "dateReserved": "2026-02-19T21:33:42.425Z", "datePublished": "2026-03-04T23:44:56.472Z", "dateUpdated": "2026-03-04T23:44:56.472Z"}, "containers": {"cna": {"affected": [{"defaultStatus": "unaffected", "product": "https://github.com/cloudflare/pingora", "repo": "https://github.com/cloudflare/pingora", "vendor": "Cloudflare", "versions": [{"lessThan": "0.8.0", "status": "affected", "version": "0", "versionType": "semver"}]}], "credits": [{"lang": "en", "type": "reporter", "value": "Rajat Raghav (xclow3n)"}], "descriptions": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<b><p><span style=\"background-color: transparent;\">A cache poisoning vulnerability has been found in the Pingora HTTP proxy framework\u2019s default cache key construction. The issue occurs because the default HTTP cache key implementation generates cache keys using only the URI path, excluding critical factors such as the host header (authority). Operators relying on the default are vulnerable to cache poisoning, and cross-origin responses may be improperly served to users.</span></p></b><br><b><p><span style=\"background-color: transparent;\">Impact</span></p><p><span style=\"background-color: transparent;\">This vulnerability affects users of Pingora's alpha proxy caching feature who relied on the default </span><span style=\"background-color: transparent;\">CacheKey</span><span style=\"background-color: transparent;\"> implementation. An attacker could exploit this for:</span></p><ul><li><p><span style=\"background-color: transparent;\">Cross-tenant data leakage: In multi-tenant deployments, poison the cache so that users from one tenant receive cached responses from another tenant</span></p></li><li><p><span style=\"background-color: transparent;\">Cache poisoning attacks: Serve malicious content to legitimate users by poisoning shared cache entries</span></p></li></ul><p><span style=\"background-color: transparent;\">Cloudflare's CDN infrastructure was not affected by this vulnerability, as Cloudflare's default cache key implementation uses multiple factors to prevent cache key poisoning and never made use of the previously provided default.</span></p></b><br><b><p><span style=\"background-color: transparent;\">Mitigation:</span></p><p><span style=\"background-color: rgb(244, 249, 250);\">We strongly recommend Pingora users to upgrade to Pingora v0.8.0 or higher, which removes the insecure default cache key implementation. Users must now explicitly implement their own callback that includes appropriate factors such as Host header, origin server HTTP scheme, and other attributes their cache should vary on.</span></p><br><p><span style=\"background-color: rgb(244, 249, 250);\">Pingora users on previous versions may also remove any of their default </span><span style=\"background-color: rgb(244, 249, 250);\">CacheKey</span><span style=\"background-color: rgb(244, 249, 250);\"> usage and implement their own that should at minimum include the host header / authority and upstream peer\u2019s HTTP scheme.</span></p></b><br><br>"}], "value": "A cache poisoning vulnerability has been found in the Pingora HTTP proxy framework\u2019s default cache key construction. The issue occurs because the default HTTP cache key implementation generates cache keys using only the URI path, excluding critical factors such as the host header (authority). Operators relying on the default are vulnerable to cache poisoning, and cross-origin responses may be improperly served to users.\n\n\nImpact\n\nThis vulnerability affects users of Pingora's alpha proxy caching feature who relied on the default CacheKey implementation. An attacker could exploit this for:\n\n * Cross-tenant data leakage: In multi-tenant deployments, poison the cache so that users from one tenant receive cached responses from another tenant\n\n\n * Cache poisoning attacks: Serve malicious content to legitimate users by poisoning shared cache entries\n\n\n\n\nCloudflare's CDN infrastructure was not affected by this vulnerability, as Cloudflare's default cache key implementation uses multiple factors to prevent cache key poisoning and never made use of the previously provided default.\n\n\nMitigation:\n\nWe strongly recommend Pingora users to upgrade to Pingora v0.8.0 or higher, which removes the insecure default cache key implementation. Users must now explicitly implement their own callback that includes appropriate factors such as Host header, origin server HTTP scheme, and other attributes their cache should vary on.\n\n\nPingora users on previous versions may also remove any of their default CacheKey usage and implement their own that should at minimum include the host header / authority and upstream peer\u2019s HTTP scheme."}], "metrics": [{"cvssV4_0": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "baseScore": 8.4, "baseSeverity": "HIGH", "exploitMaturity": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "HIGH", "subIntegrityImpact": "HIGH", "userInteraction": "PASSIVE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:H/SI:H/SA:N", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "providerMetadata": {"orgId": "a22f1246-ba21-4bb4-a601-ad51614c1513", "shortName": "cloudflare", "dateUpdated": "2026-03-04T23:44:56.472Z"}, "references": [{"url": "https://github.com/cloudflare/pingora"}], "solutions": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "We strongly recommend Pingora users to upgrade to Pingora v0.8.0 or higher<br>"}], "value": "We strongly recommend Pingora users to upgrade to Pingora v0.8.0 or higher"}], "source": {"discovery": "UNKNOWN"}, "title": "Cache poisoning via insecure-by-default cache key", "workarounds": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<b><p><span style=\"background-color: rgb(244, 249, 250);\">Pingora users on previous versions may also remove any of their default </span><span style=\"background-color: rgb(244, 249, 250);\">CacheKey</span><span style=\"background-color: rgb(244, 249, 250);\"> usage and implement their own that should at minimum include the host header / authority and upstream peer\u2019s HTTP scheme.</span></p></b>"}], "value": "Pingora users on previous versions may also remove any of their default CacheKey usage and implement their own that should at minimum include the host header / authority and upstream peer\u2019s HTTP scheme."}], "x_generator": {"engine": "Vulnogram 0.5.0"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "A cache poisoning vulnerability has been found in the Pingora HTTP proxy framework\u2019s default cache key construction. The issue occurs because the default HTTP cache key implementation generates cache keys using only the URI path, excluding critical factors such as the host header (authority). Operators relying on the default are vulnerable to cache poisoning, and cross-origin responses may be improperly served to users.\n\n\nImpact\n\nThis vulnerability affects users of Pingora's alpha proxy caching feature who relied on the default CacheKey implementation. An attacker could exploit this for:\n\n * Cross-tenant data leakage: In multi-tenant deployments, poison the cache so that users from one tenant receive cached responses from another tenant\n\n\n * Cache poisoning attacks: Serve malicious content to legitimate users by poisoning shared cache entries\n\n\n\n\nCloudflare's CDN infrastructure was not affected by this vulnerability, as Cloudflare's default cache key implementation uses multiple factors to prevent cache key poisoning and never made use of the previously provided default.\n\n\nMitigation:\n\nWe strongly recommend Pingora users to upgrade to Pingora v0.8.0 or higher, which removes the insecure default cache key implementation. Users must now explicitly implement their own callback that includes appropriate factors such as Host header, origin server HTTP scheme, and other attributes their cache should vary on.\n\n\nPingora users on previous versions may also remove any of their default CacheKey usage and implement their own that should at minimum include the host header / authority and upstream peer\u2019s HTTP scheme."}], "id": "CVE-2026-2836", "lastModified": "2026-03-05T00:15:58.053", "metrics": {"cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 8.4, "baseSeverity": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "HIGH", "subIntegrityImpact": "HIGH", "userInteraction": "PASSIVE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:H/SI:H/SA:N/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", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "cna@cloudflare.com", "type": "Secondary"}]}, "published": "2026-03-05T00:15:58.053", "references": [{"source": "cna@cloudflare.com", "url": "https://github.com/cloudflare/pingora"}], "sourceIdentifier": "cna@cloudflare.com", "vulnStatus": "Received"}

{}