{"dataType": "CVE_RECORD", "cveMetadata": {"state": "PUBLISHED", "cveId": "CVE-2026-25834", "assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca", "assignerShortName": "mitre", "dateUpdated": "2026-04-01T18:54:32.185Z", "dateReserved": "2026-02-06T00:00:00.000Z", "datePublished": "2026-04-01T00:00:00.000Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca", "shortName": "mitre", "dateUpdated": "2026-04-01T17:49:47.359Z"}, "descriptions": [{"lang": "en", "value": "Mbed TLS v3.3.0 up to 3.6.5 and 4.0.0 allows Algorithm Downgrade."}], "affected": [{"vendor": "n/a", "product": "n/a", "versions": [{"version": "n/a", "status": "affected"}]}], "references": [{"url": "https://mbed-tls.readthedocs.io/en/latest/security-advisories/"}, {"url": "https://mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-security-advisory-2026-03-sigalg-injection/"}], "problemTypes": [{"descriptions": [{"type": "text", "lang": "en", "description": "n/a"}]}]}, "adp": [{"problemTypes": [{"descriptions": [{"type": "CWE", "cweId": "CWE-295", "lang": "en", "description": "CWE-295 Improper Certificate Validation"}]}, {"descriptions": [{"type": "CWE", "cweId": "CWE-327", "lang": "en", "description": "CWE-327 Use of a Broken or Risky Cryptographic Algorithm"}]}], "metrics": [{"cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 6.5, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L", "integrityImpact": "LOW", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "LOW", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}}, {"other": {"type": "ssvc", "content": {"timestamp": "2026-04-01T18:53:56.370902Z", "id": "CVE-2026-25834", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"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": "2026-04-01T18:54:32.185Z"}}]}, "dataVersion": "5.2"}

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{"bugzilla": {"description": "mbedtls: Mbed TLS: Algorithm downgrade vulnerability", "id": "2453967", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2453967"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L", "status": "draft"}, "cwe": "CWE-358", "details": ["Mbed TLS v3.3.0 up to 3.6.5 and 4.0.0 allows Algorithm Downgrade.", "A flaw was found in Mbed TLS. A remote attacker could exploit this vulnerability by performing an algorithm downgrade attack. This could lead to a reduction in the security strength of cryptographic operations, potentially allowing for information disclosure or denial of service."], "mitigation": {"lang": "en:us", "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."}, "name": "CVE-2026-25834", "public_date": "2026-04-01T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-25834\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-25834\nhttps://mbed-tls.readthedocs.io/en/latest/security-advisories/\nhttps://mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-security-advisory-2026-03-sigalg-injection/"], "statement": "Moderate: This flaw in Mbed TLS allows a remote attacker to perform an algorithm downgrade attack, which can reduce the security strength of cryptographic operations. This could potentially lead to information disclosure or denial of service. This vulnerability affects community projects such as Fedora and EPEL.", "threat_severity": "Moderate"}