{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-75870", "assignerOrgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "state": "PUBLISHED", "assignerShortName": "CPANSec", "dateReserved": "2026-08-18T11:59:49.642Z", "datePublished": "2026-08-22T13:35:58.346Z", "dateUpdated": "2026-08-22T19:07:10.053Z"}, "containers": {"cna": {"affected": [{"collectionURL": "https://cpan.org/modules", "defaultStatus": "unaffected", "modules": ["Punk"], "packageName": "Punk", "packageURL": "pkg:cpan/Punk", "programFiles": ["xs/app.xs", "include/punk/punk_session.h"], "programRoutines": [{"name": "Punk::App::session"}, {"name": "ps_load"}, {"name": "ps_writeback"}], "versions": [{"lessThan": "0.18", "status": "affected", "version": "0", "versionType": "custom"}]}], "descriptions": [{"lang": "en", "value": "Punk versions before 0.18 for Perl allow session cookie forgery via an empty default HMAC key when a session is declared without a secret.\n\nThe session keyword freezes its options onto the application as given: it does not require a secret, warn, or refuse to start when one is absent. The cookie read and the write-back both default that key to the empty string, so a declaration with no secret option, or with an undefined or empty one, signs and verifies with a zero-length HMAC-SHA256 key.\n\nAn attacker who knows the cookie format can then mint one offline carrying any contents the session holds, such as a user identifier or a role. Nothing marks the misconfiguration at runtime: cookies are well formed and sessions round-trip as expected."}], "problemTypes": [{"descriptions": [{"cweId": "CWE-1394", "description": "CWE-1394 Use of Default Cryptographic Key", "lang": "en", "type": "CWE"}]}], "providerMetadata": {"orgId": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "shortName": "CPANSec", "dateUpdated": "2026-08-22T13:35:58.346Z"}, "references": [{"tags": ["technical-description"], "url": "https://metacpan.org/release/LNATION/Punk-0.17/source/include/punk/punk_session.h"}, {"tags": ["technical-description"], "url": "https://metacpan.org/release/LNATION/Punk-0.17/view/lib/Punk.pm"}, {"tags": ["release-notes"], "url": "https://metacpan.org/release/LNATION/Punk-0.18/source/Changes"}], "solutions": [{"lang": "en", "value": "Upgrade to Punk 0.18 or later."}], "source": {"discovery": "UNKNOWN"}, "title": "Punk versions before 0.18 for Perl allow session cookie forgery via an empty default HMAC key when a session is declared without a secret", "workarounds": [{"lang": "en", "value": "For deployments that cannot upgrade to 0.18, declare the session keyword with a non-empty secret. The secret keyword fails closed, so sourcing the key through it turns a missing configuration path or an unset environment variable into a startup error."}], "x_generator": {"engine": "cpansec-cna-tool 0.1"}}, "adp": [{"title": "CVE Program Container", "references": [{"url": "http://www.openwall.com/lists/oss-security/2026/08/22/5"}], "providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2026-08-22T19:07:10.053Z"}}]}}

{}

{"affected": [{"affectedData": [{"collectionURL": "https://cpan.org/modules", "defaultStatus": "unaffected", "modules": ["Punk"], "packageName": "Punk", "packageURL": "pkg:cpan/Punk", "programFiles": ["xs/app.xs", "include/punk/punk_session.h"], "programRoutines": [{"name": "Punk::App::session"}, {"name": "ps_load"}, {"name": "ps_writeback"}], "versions": [{"lessThan": "0.18", "status": "affected", "version": "0", "versionType": "custom"}]}], "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Punk versions before 0.18 for Perl allow session cookie forgery via an empty default HMAC key when a session is declared without a secret.\n\nThe session keyword freezes its options onto the application as given: it does not require a secret, warn, or refuse to start when one is absent. The cookie read and the write-back both default that key to the empty string, so a declaration with no secret option, or with an undefined or empty one, signs and verifies with a zero-length HMAC-SHA256 key.\n\nAn attacker who knows the cookie format can then mint one offline carrying any contents the session holds, such as a user identifier or a role. Nothing marks the misconfiguration at runtime: cookies are well formed and sessions round-trip as expected."}], "id": "CVE-2026-75870", "lastModified": "2026-08-22T19:16:20.430", "metrics": {}, "published": "2026-08-22T14:16:33.813", "references": [{"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "url": "https://metacpan.org/release/LNATION/Punk-0.17/source/include/punk/punk_session.h"}, {"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "url": "https://metacpan.org/release/LNATION/Punk-0.17/view/lib/Punk.pm"}, {"source": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "url": "https://metacpan.org/release/LNATION/Punk-0.18/source/Changes"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "url": "http://www.openwall.com/lists/oss-security/2026/08/22/5"}], "sourceIdentifier": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-1394"}], "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "type": "Secondary"}]}

{}

{"created": "2026-08-22T14:45:03.354852+00:00", "updated": "2026-08-22T14:45:03.354864+00:00", "vendors": []}