{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-11850","assignerOrgId":"53f830b8-0a3f-465b-8143-3b8a9948e749","state":"PUBLISHED","assignerShortName":"redhat","dateReserved":"2026-06-10T08:12:34.560Z","datePublished":"2026-06-11T09:49:07.726Z","dateUpdated":"2026-07-06T22:00:32.492Z"},"containers":{"cna":{"title":"Krb5: krb5: integer underflow in berval2tl_data() leads to heap out-of-bounds read","metrics":[{"other":{"content":{"value":"Moderate","namespace":"https://access.redhat.com/security/updates/classification/"},"type":"Red Hat severity rating"}},{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":5,"baseSeverity":"MEDIUM","confidentialityImpact":"LOW","integrityImpact":"NONE","privilegesRequired":"HIGH","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:L/I:N/A:H","version":"3.1"},"format":"CVSS"}],"descriptions":[{"lang":"en","value":"An integer underflow vulnerability was found in MIT krb5 in the berval2tl_data() function in plugins/kdb/ldap/libkdb_ldap/ldap_principal2.c. The function performs an unsigned subtraction (bv_len - 2) without a prior bounds check. When bv_len is 0 or 1, the subtraction wraps to a large value which is then truncated to uint16_t, yielding 0xFFFE (65534) or 0xFFFF (65535). The subsequent malloc succeeds and memcpy reads up to 65534 bytes from a 0-1 byte buffer, resulting in a heap out-of-bounds read.\nThe attack vector involves a malicious or compromised LDAP KDB backend returning a krbExtraData attribute with bv_len < 2, triggering the underflow when the KDC or kadmind reads principal data."}],"affected":[{"vendor":"Red Hat","product":"Red Hat Hardened Images","collectionURL":"https://catalog.redhat.com/software/containers/","packageName":"krb5-main","defaultStatus":"affected","versions":[{"version":"1.22.2-8.hum1","lessThan":"*","versionType":"rpm","status":"unaffected"}],"cpes":["cpe:/a:redhat:hummingbird:1"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 10","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"krb5","defaultStatus":"affected","cpes":["cpe:/o:redhat:enterprise_linux:10"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 6","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"krb5","defaultStatus":"affected","cpes":["cpe:/o:redhat:enterprise_linux:6"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 7","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"krb5","defaultStatus":"affected","cpes":["cpe:/o:redhat:enterprise_linux:7"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 8","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"krb5","defaultStatus":"affected","cpes":["cpe:/o:redhat:enterprise_linux:8"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"krb5","defaultStatus":"affected","cpes":["cpe:/o:redhat:enterprise_linux:9"]},{"vendor":"Red Hat","product":"Red Hat OpenShift Container Platform 4","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","packageName":"rhcos","defaultStatus":"affected","cpes":["cpe:/a:redhat:openshift:4"]}],"references":[{"url":"https://access.redhat.com/errata/RHSA-2026:25520","name":"RHSA-2026:25520","tags":["vendor-advisory","x_refsource_REDHAT"]},{"url":"https://access.redhat.com/security/cve/CVE-2026-11850","tags":["vdb-entry","x_refsource_REDHAT"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2459970","name":"RHBZ#2459970","tags":["issue-tracking","x_refsource_REDHAT"]}],"datePublic":"2026-06-10T00:00:00.000Z","problemTypes":[{"descriptions":[{"cweId":"CWE-191","description":"Integer Underflow (Wrap or Wraparound)","lang":"en","type":"CWE"}]}],"x_redhatCweChain":"CWE-191: Integer Underflow (Wrap or Wraparound)","workarounds":[{"lang":"en","value":"Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability."}],"timeline":[{"lang":"en","time":"2026-04-21T00:00:00.000Z","value":"Reported to Red Hat."},{"lang":"en","time":"2026-06-10T00:00:00.000Z","value":"Made public."}],"credits":[{"lang":"en","value":"Red Hat would like to thank Sebastián Alba Vives for reporting this issue."}],"providerMetadata":{"orgId":"53f830b8-0a3f-465b-8143-3b8a9948e749","shortName":"redhat","dateUpdated":"2026-07-06T22:00:32.492Z"},"x_generator":{"engine":"cvelib 1.8.0"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-11T12:35:21.860008Z","id":"CVE-2026-11850","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-06-11T12:37:05.721Z"}}]}}