{"id":"CVE-2023-3603","state":"PUBLISHED","title":"Processing sftp server read may cause null dereference","description":"A missing allocation check in sftp server processing read requests may cause a NULL dereference on low-memory conditions. The malicious client can request up to 4GB SFTP reads, causing allocation of up to 4GB buffers, which was not being checked for failure. This will likely crash the authenticated user's sftp server connection (if implemented as forking as recommended). For thread-based servers, this might also cause DoS for legitimate users.\r\n\r\nGiven this code is not in any released versions, no security releases have been issued.","publishedAt":"2023-07-21T19:09:44.083Z","updatedAt":"2024-09-26T20:04:43.251Z","severity":{"score":3.1,"label":"Low","version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L","source":"redhat"},"assigner":"redhat","products":["n/a libssh","Red Hat Red Hat Enterprise Linux 7","Red Hat Red Hat Enterprise Linux 8","Red Hat Red Hat Enterprise Linux 9","Fedora Extra Packages for Enterprise Linux 7","Fedora Fedora"],"affected":[{"vendor":"n/a","product":"libssh","defaultStatus":"affected"},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 7","packageName":"libssh","defaultStatus":"unaffected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:7"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 8","packageName":"libssh","defaultStatus":"unaffected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:8"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","packageName":"libssh","defaultStatus":"unaffected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:9"]},{"vendor":"Fedora","product":"Extra Packages for Enterprise Linux 7","packageName":"libssh","defaultStatus":"unaffected","collectionURL":"https://packages.fedoraproject.org/"},{"vendor":"Fedora","product":"Fedora","packageName":"libssh","defaultStatus":"unaffected","collectionURL":"https://packages.fedoraproject.org/"}],"references":["https://access.redhat.com/security/cve/CVE-2023-3603","https://bugzilla.redhat.com/show_bug.cgi?id=2221791"],"weaknesses":["CWE-476"],"ingestedAt":"2026-10-29T20:06:08.715Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2023/3xxx/CVE-2023-3603.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.1","cveMetadata":{"cveId":"CVE-2023-3603","state":"PUBLISHED","datePublished":"2023-07-21T19:09:44.083Z","dateUpdated":"2024-09-26T20:04:43.251Z","assignerShortName":"redhat","assignerOrgId":"53f830b8-0a3f-465b-8143-3b8a9948e749","dateReserved":"2023-07-10T18:21:21.431Z"},"containers":{"cna":{"title":"Processing sftp server read may cause null dereference","descriptions":[{"lang":"en","value":"A missing allocation check in sftp server processing read requests may cause a NULL dereference on low-memory conditions. The malicious client can request up to 4GB SFTP reads, causing allocation of up to 4GB buffers, which was not being checked for failure. This will likely crash the authenticated user's sftp server connection (if implemented as forking as recommended). For thread-based servers, this might also cause DoS for legitimate users.\r\n\r\nGiven this code is not in any released versions, no security releases have been issued."}],"affected":[{"vendor":"n/a","product":"libssh","defaultStatus":"affected"},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 7","packageName":"libssh","defaultStatus":"unaffected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:7"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 8","packageName":"libssh","defaultStatus":"unaffected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:8"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","packageName":"libssh","defaultStatus":"unaffected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:9"]},{"vendor":"Fedora","product":"Extra Packages for Enterprise Linux 7","packageName":"libssh","defaultStatus":"unaffected","collectionURL":"https://packages.fedoraproject.org/"},{"vendor":"Fedora","product":"Fedora","packageName":"libssh","defaultStatus":"unaffected","collectionURL":"https://packages.fedoraproject.org/"}],"references":[{"url":"https://access.redhat.com/security/cve/CVE-2023-3603","tags":["vdb-entry","x_refsource_REDHAT"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2221791","name":"RHBZ#2221791","tags":["issue-tracking","x_refsource_REDHAT"]}],"metrics":[{"other":{"content":{"value":"Low","namespace":"https://access.redhat.com/security/updates/classification/"},"type":"Red Hat severity rating"}},{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":3.1,"baseSeverity":"LOW","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L","version":"3.1"},"format":"CVSS"}],"problemTypes":[{"descriptions":[{"cweId":"CWE-476","description":"NULL Pointer Dereference","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"redhat","orgId":"53f830b8-0a3f-465b-8143-3b8a9948e749","dateUpdated":"2024-01-23T00:58:36.996Z"},"datePublic":"2023-07-10T00:00:00.000Z","x_redhatCweChain":"CWE-476: NULL Pointer Dereference","workarounds":[{"lang":"en","value":"The SFTP server implementation is based on callbacks so you can rewrite the sftp_channel_default_data_callback() to provide additional checks.\n\n[1] https://gitlab.com/libssh/libssh-mirror/-/blob/master/examples/sample_sftpserver.c#L330"}],"timeline":[{"lang":"en","time":"2023-07-10T00:00:00.000Z","value":"Reported to Red Hat."},{"lang":"en","time":"2023-07-10T00:00:00.000Z","value":"Made public."}],"credits":[{"lang":"en","value":"Upstream acknowledges Wei Chong Tan as the original reporter."}]},"adp":[{"title":"CVE Program Container","references":[{"url":"https://access.redhat.com/security/cve/CVE-2023-3603","tags":["vdb-entry","x_refsource_REDHAT","x_transferred"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2221791","name":"RHBZ#2221791","tags":["issue-tracking","x_refsource_REDHAT","x_transferred"]}],"providerMetadata":{"shortName":"CVE","orgId":"af854a3a-2127-422b-91ae-364da2661108","dateUpdated":"2024-08-02T07:01:56.718Z"}},{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2024-09-26T20:04:28.247195Z","id":"CVE-2023-3603","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2024-09-26T20:04:43.251Z"}}]}}}