{"id":"CVE-2026-110672","kind":"vulnerability","aliases":["CVE-2026-110672"],"related":[],"title":"Cpanel::JSON::XS: rejected JSON objects leak memory, repeated requests exhaust process memory","description":"Cpanel::JSON::XS versions before 4.80 for Perl leak the decoded key of an object rejected for a duplicate key or a missing colon in decode_hv.\n\nA quoted key of 24 or more bytes, or one containing a non-ASCII byte or an escape sequence, is decoded into a new scalar. Nothing frees that scalar when the object is rejected for a missing ':' after the key or, from 4.09, for a duplicate key. Duplicate keys are an error unless allow_dupkeys, dupkeys_as_arrayref or relaxed is set.\n\nA process that keeps running after a failed decode retains one key per rejected document, with its size chosen by the sender. Repeated requests exhaust process memory.","summary":"Cpanel::JSON::XS before 4.80 for Perl leaks the decoded key of a JSON object rejected for a duplicate key or a missing colon. A long-running process that keeps handling bad documents accumulates one leaked key per rejected document, so repeated requests can exhaust its memory.","severity":"medium","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["cpanel-json-xs","package","perl","self-hosted","web-services"],"not_affected_if":["not-installed","short-lived-processes","trusted-input-only"],"how_to_check":"- Check the installed version with `perl -MCpanel::JSON::XS -e 'print $Cpanel::JSON::XS::VERSION'`, or `cpanm --info Cpanel::JSON::XS`.\n- Search dependency manifests and lockfiles for `Cpanel::JSON::XS` below `4.80`.\n- Check whether decode calls leave out allow_dupkeys, dupkeys_as_arrayref and relaxed, and whether the process accepts untrusted JSON for a long time.","fix":"- Upgrade Cpanel::JSON::XS to `4.80` or later.\n- Restart long-running worker processes after upgrading so leaked memory is released.","status":"open","published_at":"2026-10-19T19:17:20+00:00","first_seen_at":"2026-10-23T21:57:18+00:00","triaged_at":"2026-10-25T05:10:54+00:00","updated_at":"2026-10-25T05:10:54+00:00","category":"package","confidence":0.7,"triage":{"at":"2026-10-25T05:10:54Z","model":"claude-haiku-5-5","output":{"fix":"- Upgrade Cpanel::JSON::XS to `4.80` or later.\n- Restart long-running worker processes after upgrading so leaked memory is released.","reach":"internet","title":"Cpanel::JSON::XS: rejected JSON objects leak memory, repeated requests exhaust process memory","impact":"medium","summary":"Cpanel::JSON::XS before 4.80 for Perl leaks the decoded key of a JSON object rejected for a duplicate key or a missing colon. A long-running process that keeps handling bad documents accumulates one leaked key per rejected document, so repeated requests can exhaust its memory.","category":"package","nicknames":[],"who_cares":["perl","cpanel-json-xs","self-hosted","web-services"],"confidence":0.7,"needs_auth":"unknown","worst_case":"Repeated malformed requests exhaust process memory and crash the service","analyst_note":"Confirm the fixed version and whether a patched release is published on CPAN; the sources give only the 4.80 boundary and no CVSS score.","how_to_check":"- Check the installed version with `perl -MCpanel::JSON::XS -e 'print $Cpanel::JSON::XS::VERSION'`, or `cpanm --info Cpanel::JSON::XS`.\n- Search dependency manifests and lockfiles for `Cpanel::JSON::XS` below `4.80`.\n- Check whether decode calls leave out allow_dupkeys, dupkeys_as_arrayref and relaxed, and whether the process accepts untrusted JSON for a long time.","needs_analyst":true,"not_affected_if":["short-lived-processes","trusted-input-only","not-installed"],"who_is_affected":"Perl applications that decode untrusted JSON with Cpanel::JSON::XS in a process that keeps running after a failed decode, such as a web service, daemon or queue worker. Short-lived scripts that exit after each decode are not meaningfully exposed. Systems that never parse untrusted JSON with this module can skip it.","user_interaction":"no","needs_special_setup":"no","severity_if_unknown":"medium"},"cost_usd":0.000714,"input_tokens":3457,"output_tokens":737,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-110672':16A,19A '-2026':15A,18A '24':111C '4.09':150C '4.80':36B,85C 'accumul':66B 'allow':161C 'arrayref':165C 'ascii':121C 'bad':64B 'byte':114C,122C 'chosen':188C 'colon':55B,103C 'contain':117C 'cpanel':1A,21B,32B,80C 'cpanel-json-x':20B 'cve':14A,17A 'decod':41B,90C,105C,128C,178C 'document':65B,72B,184C 'dupkey':162C,163C 'duplic':50B,98C,153C,155C 'error':159C 'escap':125C 'exhaust':11A,77B,194C 'fail':177C 'free':134C 'handl':63B 'host':28B 'hv':106C 'json':2A,5A,22B,33B,45B,81C 'keep':62B,173C 'key':42B,51B,69B,91C,99C,109C,147C,154C,156C,181C 'leak':7A,39B,68B,88C 'long':58B 'long-run':57B 'memori':8A,13A,79B,196C 'miss':54B,102C,144C 'new':131C 'non':120C 'non-ascii':119C 'noth':133C 'object':6A,46B,94C,139C 'one':67B,116C,180C 'packag':24B 'per':70B,182C 'perl':25B,38B,87C 'process':12A,60B,171C,195C 'quot':108C 'reject':4A,47B,71B,95C,141C,183C 'relax':167C 'repeat':9A,74B,192C 'request':10A,75B,193C 'retain':179C 'run':59B,174C 'scalar':132C,136C 'self':27B 'self-host':26B 'sender':191C 'sequenc':126C 'servic':31B 'set':169C 'size':187C 'unless':160C 'version':83C 'web':30B 'web-servic':29B 'xs':3A,23B,34B,82C","nicknames":[],"mitigations":[],"who_affected":"Perl applications that decode untrusted JSON with Cpanel::JSON::XS in a process that keeps running after a failed decode, such as a web service, daemon or queue worker. Short-lived scripts that exit after each decode are not meaningfully exposed. Systems that never parse untrusted JSON with this module can skip it.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-19T19:17:20+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-110672","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-110672","severity":null,"published_at":"2026-10-19T19:17:20+00:00","modified_at":"2026-10-19T20:50:17+00:00","first_seen_at":"2026-10-23T21:57:18+00:00","fetched_at":"2026-10-23T22:28:57+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}