{"api_version":"1","generated_at":"2026-04-22T19:51:59+00:00","cve":"CVE-2023-31137","urls":{"html":"https://cve.report/CVE-2023-31137","api":"https://cve.report/api/cve/CVE-2023-31137.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2023-31137","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2023-31137"},"summary":{"title":"CVE-2023-31137","description":"MaraDNS is open-source software that implements the Domain Name System (DNS). In version 3.5.0024 and prior, a remotely exploitable integer underflow vulnerability in the DNS packet decompression function allows an attacker to cause a Denial of Service by triggering an abnormal program termination.\n\nThe vulnerability exists in the `decomp_get_rddata` function within the `Decompress.c` file. When handling a DNS packet with an Answer RR of qtype 16 (TXT record) and any qclass, if the `rdlength` is smaller than `rdata`, the result of the line `Decompress.c:886` is a negative number `len = rdlength - total;`. This value is then passed to the `decomp_append_bytes` function without proper validation, causing the program to attempt to allocate a massive chunk of memory that is impossible to allocate. Consequently, the program exits with an error code of 64, causing a Denial of Service.\n\nOne proposed fix for this vulnerability is to patch `Decompress.c:887` by breaking `if(len <= 0)`, which has been incorporated in version 3.5.0036 via commit bab062bde40b2ae8a91eecd522e84d8b993bab58.","state":"PUBLIC","assigner":"security-advisories@github.com","published_at":"2023-05-09 14:15:00","updated_at":"2023-06-29 12:15:00"},"problem_types":["CWE-191"],"metrics":[],"references":[{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NB7LDZM5AGWC5BHHQHW6CP5OFNBBKFOQ/","name":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NB7LDZM5AGWC5BHHQHW6CP5OFNBBKFOQ/","refsource":"MISC","tags":[],"title":"[SECURITY] Fedora 38 Update: maradns-3.5.0036-1.fc38 - package-announce - Fedora Mailing-Lists","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/3VSMLJX25MXGQ6A7UPOGK7VPUVDESPHL/","name":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/3VSMLJX25MXGQ6A7UPOGK7VPUVDESPHL/","refsource":"MISC","tags":[],"title":"[SECURITY] Fedora 37 Update: maradns-3.5.0036-1.fc37 - package-announce - Fedora Mailing-Lists","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://github.com/samboy/MaraDNS/security/advisories/GHSA-58m7-826v-9c3c","name":"https://github.com/samboy/MaraDNS/security/advisories/GHSA-58m7-826v-9c3c","refsource":"MISC","tags":[],"title":"Integer Underflow Vulnerability in DNS Packet Decompression · Advisory · samboy/MaraDNS · GitHub","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://github.com/samboy/MaraDNS/commit/bab062bde40b2ae8a91eecd522e84d8b993bab58","name":"https://github.com/samboy/MaraDNS/commit/bab062bde40b2ae8a91eecd522e84d8b993bab58","refsource":"MISC","tags":[],"title":"Fix long standing issue in this code from 2002 · samboy/MaraDNS@bab062b · GitHub","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://github.com/samboy/MaraDNS/blob/08b21ea20d80cedcb74aa8f14979ec7c61846663/dns/Decompress.c#L886","name":"https://github.com/samboy/MaraDNS/blob/08b21ea20d80cedcb74aa8f14979ec7c61846663/dns/Decompress.c#L886","refsource":"MISC","tags":[],"title":"MaraDNS/Decompress.c at 08b21ea20d80cedcb74aa8f14979ec7c61846663 · samboy/MaraDNS · GitHub","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://www.debian.org/security/2023/dsa-5441","name":"https://www.debian.org/security/2023/dsa-5441","refsource":"MISC","tags":[],"title":"Debian -- Security Information -- DSA-5441-1 maradns","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://lists.debian.org/debian-lts-announce/2023/06/msg00019.html","name":"https://lists.debian.org/debian-lts-announce/2023/06/msg00019.html","refsource":"MISC","tags":[],"title":"[SECURITY] [DLA 3457-1] maradns security update","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://www.cve.org/CVERecord?id=CVE-2023-31137","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-31137","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[{"cve_year":"2023","cve_id":"31137","vulnerable":"1","versionEndIncluding":"3.5.0024","cpe1":"cpe","cpe2":"2.3","cpe3":"a","cpe4":"maradns","cpe5":"maradns","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"}],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[{"cve":"CVE-2023-31137","qid":"181878","title":"Debian Security Update for maradns (DLA 3457-1)"},{"cve":"CVE-2023-31137","qid":"199635","title":"Ubuntu Security Notification for Mara Domain Name System (DNS) Vulnerabilities (USN-6271-1)"},{"cve":"CVE-2023-31137","qid":"283996","title":"Fedora Security Update for maradns (FEDORA-2023-cdce244fb8)"},{"cve":"CVE-2023-31137","qid":"284134","title":"Fedora Security Update for maradns (FEDORA-2023-0c012f6245)"},{"cve":"CVE-2023-31137","qid":"285314","title":"Fedora Security Update for maradns (FEDORA-2023-3dd938a14d)"},{"cve":"CVE-2023-31137","qid":"6000241","title":"Debian Security Update for maradns (DSA 5441-1)"}]},"source_records":{"cve_program":{"data_version":"4.0","data_type":"CVE","data_format":"MITRE","CVE_data_meta":{"ID":"CVE-2023-31137","ASSIGNER":"security-advisories@github.com","STATE":"PUBLIC"},"description":{"description_data":[{"lang":"eng","value":"MaraDNS is open-source software that implements the Domain Name System (DNS). In version 3.5.0024 and prior, a remotely exploitable integer underflow vulnerability in the DNS packet decompression function allows an attacker to cause a Denial of Service by triggering an abnormal program termination.\n\nThe vulnerability exists in the `decomp_get_rddata` function within the `Decompress.c` file. When handling a DNS packet with an Answer RR of qtype 16 (TXT record) and any qclass, if the `rdlength` is smaller than `rdata`, the result of the line `Decompress.c:886` is a negative number `len = rdlength - total;`. This value is then passed to the `decomp_append_bytes` function without proper validation, causing the program to attempt to allocate a massive chunk of memory that is impossible to allocate. Consequently, the program exits with an error code of 64, causing a Denial of Service.\n\nOne proposed fix for this vulnerability is to patch `Decompress.c:887` by breaking `if(len <= 0)`, which has been incorporated in version 3.5.0036 via commit bab062bde40b2ae8a91eecd522e84d8b993bab58."}]},"problemtype":{"problemtype_data":[{"description":[{"lang":"eng","value":"CWE-191: Integer Underflow (Wrap or Wraparound)","cweId":"CWE-191"}]}]},"affects":{"vendor":{"vendor_data":[{"vendor_name":"samboy","product":{"product_data":[{"product_name":"MaraDNS","version":{"version_data":[{"version_affected":"=","version_value":"<= 3.5.0024"}]}}]}}]}},"references":{"reference_data":[{"url":"https://github.com/samboy/MaraDNS/security/advisories/GHSA-58m7-826v-9c3c","refsource":"MISC","name":"https://github.com/samboy/MaraDNS/security/advisories/GHSA-58m7-826v-9c3c"},{"url":"https://github.com/samboy/MaraDNS/commit/bab062bde40b2ae8a91eecd522e84d8b993bab58","refsource":"MISC","name":"https://github.com/samboy/MaraDNS/commit/bab062bde40b2ae8a91eecd522e84d8b993bab58"},{"url":"https://github.com/samboy/MaraDNS/blob/08b21ea20d80cedcb74aa8f14979ec7c61846663/dns/Decompress.c#L886","refsource":"MISC","name":"https://github.com/samboy/MaraDNS/blob/08b21ea20d80cedcb74aa8f14979ec7c61846663/dns/Decompress.c#L886"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NB7LDZM5AGWC5BHHQHW6CP5OFNBBKFOQ/","refsource":"MISC","name":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NB7LDZM5AGWC5BHHQHW6CP5OFNBBKFOQ/"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/3VSMLJX25MXGQ6A7UPOGK7VPUVDESPHL/","refsource":"MISC","name":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/3VSMLJX25MXGQ6A7UPOGK7VPUVDESPHL/"},{"url":"https://lists.debian.org/debian-lts-announce/2023/06/msg00019.html","refsource":"MISC","name":"https://lists.debian.org/debian-lts-announce/2023/06/msg00019.html"},{"url":"https://www.debian.org/security/2023/dsa-5441","refsource":"MISC","name":"https://www.debian.org/security/2023/dsa-5441"}]},"source":{"advisory":"GHSA-58m7-826v-9c3c","discovery":"UNKNOWN"},"impact":{"cvss":[{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}]}},"nvd":{"publishedDate":"2023-05-09 14:15:00","lastModifiedDate":"2023-06-29 12:15:00","problem_types":["CWE-191"],"metrics":{"baseMetricV3":{"cvssV3":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH"},"exploitabilityScore":3.9,"impactScore":3.6}},"configurations":{"CVE_data_version":"4.0","nodes":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:maradns:maradns:*:*:*:*:*:*:*:*","versionEndIncluding":"3.5.0024","cpe_name":[]}]}]}},"legacy_mitre":{"record":null,"notes":[]}}}