{"id":"CVE-2022-0028","kind":"vulnerability","aliases":["CVE-2022-0028"],"related":[],"title":"paloaltonetworks pan-os: A PAN-OS URL filtering policy misconfiguration could allow a network-based attacker to conduct reflected and…","description":"A PAN-OS URL filtering policy misconfiguration could allow a network-based attacker to conduct reflected and amplified TCP denial-of-service (RDoS) attacks. The DoS attack would appear to originate from a Palo Alto Networks PA-Series (hardware), VM-Series (virtual) and CN-Series (container) firewall against an attacker-specified target. To be misused by an external attacker, the firewall configuration must have a URL filtering profile with one or more blocked categories assigned to a source zone that has an external facing interface. This configuration is not typical for URL filtering and, if set, is likely unintended by the administrator. If exploited, this issue would not impact the confidentiality, integrity, or availability of our products. However, the resulting denial-of-service (DoS) attack may help obfuscate the identity of the attacker and implicate the firewall as the source of the attack. We have taken prompt action to address this issue in our PAN-OS software. All software updates for this issue are expected to be released no later than the week of August 15, 2022. This issue does not impact Panorama M-Series or Panorama virtual appliances. This issue has been resolved for all Cloud NGFW and Prisma Access customers and no additional action is required from them.","summary":"A URL filtering policy misconfiguration in Palo Alto Networks PAN-OS lets a network attacker bounce and amplify TCP traffic at third parties, a reflected denial-of-service. The sources say it is actively exploited, per CISA's KEV catalog.","severity":"high","cvss":8.6,"epss":0.02542,"exploited":true,"exploited_at":"2022-08-22T00:00:00+00:00","products":[{"name":"Palo Alto Networks PAN-OS","fixed":[],"affected":"","ecosystem":"vendor"},{"name":"paloaltonetworks pan-os","fixed":["8.1.23"],"affected":">= 8.1.0, < 8.1.23","ecosystem":"vendor"},{"name":"paloaltonetworks pan-os","fixed":["9.0.16"],"affected":">= 9.0.0, < 9.0.16","ecosystem":"vendor"},{"name":"paloaltonetworks pan-os","fixed":["9.1.14"],"affected":">= 9.1.0, < 9.1.14","ecosystem":"vendor"},{"name":"paloaltonetworks pan-os","fixed":["10.0.11"],"affected":">= 10.0.0, < 10.0.11","ecosystem":"vendor"},{"name":"paloaltonetworks pan-os","fixed":["10.1.6"],"affected":">= 10.1.0, < 10.1.6","ecosystem":"vendor"},{"name":"paloaltonetworks pan-os","fixed":["10.2.2"],"affected":">= 10.2.0, < 10.2.2","ecosystem":"vendor"},{"name":"paloaltonetworks pan-os","fixed":[],"affected":"= 8.1.23","ecosystem":"vendor"},{"name":"paloaltonetworks pan-os","fixed":[],"affected":"= 9.0.16","ecosystem":"vendor"},{"name":"paloaltonetworks pan-os","fixed":[],"affected":"= 9.1.14","ecosystem":"vendor"},{"name":"paloaltonetworks pan-os","fixed":[],"affected":"= 10.0.11","ecosystem":"vendor"},{"name":"paloaltonetworks pan-os","fixed":[],"affected":"= 10.1.6","ecosystem":"vendor"},{"name":"paloaltonetworks pan-os","fixed":[],"affected":"= 10.2.2","ecosystem":"vendor"}],"ecosystems":["vendor"],"tags":["exploited","firewall","infrastructure","palo-alto-networks","pan-os"],"not_affected_if":["no-pan-os-firewall","url-filtering-policy-not-misconfigured"],"how_to_check":null,"fix":"Apply updates per vendor instructions (CISA KEV required action); the specific fixed PAN-OS versions are unknown from the sources.","status":"open","published_at":"2022-08-10T16:15:08+00:00","first_seen_at":"2026-10-23T19:11:52+00:00","triaged_at":"2026-10-23T21:10:55+00:00","updated_at":"2026-10-23T22:29:04+00:00","category":"infrastructure","confidence":0.5,"triage":{"at":"2026-10-23T21:10:55Z","model":"claude-haiku-5-5","output":{"fix":"Apply updates per vendor instructions (CISA KEV required action); the specific fixed PAN-OS versions are unknown from the sources.","reach":"network","impact":"medium","summary":"A URL filtering policy misconfiguration in Palo Alto Networks PAN-OS lets a network attacker bounce and amplify TCP traffic at third parties, a reflected denial-of-service. The sources say it is actively exploited, per CISA's KEV catalog.","category":"infrastructure","who_cares":["palo-alto-networks","pan-os","firewall"],"confidence":0.5,"needs_auth":"unknown","worst_case":"Firewall is abused to flood third-party hosts with amplified TCP traffic","analyst_note":"Find the affected and fixed PAN-OS versions and the Palo Alto advisory for CVE-2022-0028 and the exact URL filtering misconfiguration to check for.","how_to_check":"unknown","needs_analyst":true,"not_affected_if":["no-pan-os-firewall","url-filtering-policy-not-misconfigured"],"user_interaction":"no","needs_special_setup":"yes","severity_if_unknown":"medium"},"cost_usd":0.000492,"input_tokens":2876,"output_tokens":409,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-0028':25A,28A '-2022':24A,27A '15':319C '2022':320C 'access':345C 'action':290C,350C 'activ':128B 'addit':349C 'address':292C 'administr':243C 'allow':14A,144C 'alto':30A,88B,100B,172C 'amplifi':111B,154C 'appear':166C 'applianc':333C 'assign':216C 'attack':19A,108B,149C,161C,164C,191C,200C,267C,275C,285C 'attacker-specifi':190C 'august':318C 'avail':255C 'base':18A,148C 'block':214C 'bounc':109B 'catalog':134B 'categori':215C 'cisa':131B 'cloud':341C 'cn':184C 'cn-seri':183C 'conduct':21A,151C 'confidenti':252C 'configur':203C,228C 'contain':186C 'could':13A,143C 'custom':346C 'cve':23A,26A 'denial':120B,157C,263C 'denial-of-servic':119B,156C,262C 'dos':163C,266C 'expect':308C 'exploit':83B,129B,245C 'extern':199C,224C 'face':225C 'filter':10A,95B,140C,208C,234C 'firewal':84B,187C,202C,279C 'hardwar':177C 'help':269C 'howev':259C 'ident':272C 'impact':250C,325C 'implic':277C 'infrastructur':85B 'integr':253C 'interfac':226C 'issu':247C,294C,306C,322C,335C 'kev':133B 'later':313C 'let':105B 'like':239C 'm':328C 'm-seri':327C 'may':268C 'misconfigur':12A,97B,142C 'misus':196C 'must':204C 'network':17A,89B,101B,107B,147C,173C 'network-bas':16A,146C 'networks':31A 'ngfw':342C 'obfusc':270C 'one':211C 'origin':168C 'os':4A,8A,34A,38A,42A,46A,50A,54A,58A,62A,66A,70A,74A,78A,82A,92B,104B,138C,299C 'pa':175C 'pa-seri':174C 'palo':29A,87B,99B,171C 'palo-alto-network':86B 'paloaltonetwork':1A 'paloaltonetworks':35A,39A,43A,47A,51A,55A,59A,63A,67A,71A,75A,79A 'pan':3A,7A,33A,37A,41A,45A,49A,53A,57A,61A,65A,69A,73A,77A,81A,91B,103B,137C,298C 'pan-o':2A,6A,90B,102B,136C,297C 'pan-os':32A,36A,40A,44A,48A,52A,56A,60A,64A,68A,72A,76A,80A 'panorama':326C,331C 'parti':116B 'per':130B 'polici':11A,96B,141C 'prisma':344C 'product':258C 'profil':209C 'prompt':289C 'rdos':160C 'reflect':22A,118B,152C 'releas':311C 'requir':352C 'resolv':338C 'result':261C 'say':125B 'seri':176C,180C,185C,329C 'servic':122B,159C,265C 'set':237C 'softwar':300C,302C 'sourc':124B,219C,282C 'specifi':192C 'taken':288C 'target':193C 'tcp':112B,155C 'third':115B 'traffic':113B 'typic':231C 'unintend':240C 'updat':303C 'url':9A,94B,139C,207C,233C 'virtual':181C,332C 'vm':179C 'vm-seri':178C 'week':316C 'would':165C,248C 'zone':220C","nicknames":[],"mitigations":[],"who_affected":null,"tier":null,"verified":{},"analyst_revisit_at":null,"first_public_at":"2022-08-10T16:15:08+00:00","kev":{"dateAdded":"2022-08-22","dueDate":"2022-09-12","requiredAction":"Apply updates per vendor instructions.","knownRansomwareCampaignUse":"Unknown"},"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","cvss_by":"psirt@paloaltonetworks.com","poc_count":0,"sources":[{"source":"kev","external_id":"CVE-2022-0028","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2022-0028","severity":null,"published_at":"2022-08-22T00:00:00+00:00","modified_at":null,"first_seen_at":"2026-10-23T19:11:52+00:00","fetched_at":"2026-10-25T11:39:16+00:00","note":null},{"source":"epss","external_id":"CVE-2022-0028","url":"https://api.first.org/data/v1/epss?cve=CVE-2022-0028","severity":null,"published_at":null,"modified_at":null,"first_seen_at":"2026-10-23T19:13:45+00:00","fetched_at":"2026-10-23T19:13:45+00:00","note":null},{"source":"nvd","external_id":"CVE-2022-0028","url":"https://nvd.nist.gov/vuln/detail/CVE-2022-0028","severity":null,"published_at":"2022-08-10T16:15:08+00:00","modified_at":"2026-06-17T04:19:55+00:00","first_seen_at":"2026-10-23T22:29:04+00:00","fetched_at":"2026-10-23T22:29:04+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"}