Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8d89a3d682f19ab…

MALICIOUS

PDF

82.8 KB Created: 2021-09-17 09:46:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: e0b57f9cae916b4b17135ed01f695351 SHA-1: b8b15e1033d9316caea4882cbcb9ee5c0189dbfb SHA-256: a8d89a3d682f19abeed2a770e2b395cf2eab7d6ebea5792654571414ceca714f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. The presence of multiple compromised CMS upload links suggests an attempt to host malicious content on seemingly legitimate but compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://medvor.ru/uplcv?utm_term=the+lottery+by+shirley+jackson+summary+pdf PDF link annotation
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fcda03abd9---dikutuvigubotobofip.pdfIn PDF document text
    • http://intimatehotelpattaya.com/image/upload/File/57581689274.pdfIn PDF document text
    • http://jonkmp.nl/img/cms/file/nubimetimoxamegufevufumuk.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161422e4a9b3b9---67755541543.pdfIn PDF document text
    • http://irvinenott.co.uk/ckfinder/userfiles/files/96756006083.pdfIn PDF document text
    • http://huefpdf.org/upload/file/20338810812.pdfIn PDF document text
    • http://positiveforce.in/uploads/files/58475619383.pdfIn PDF document text
    • https://youxsoft.com/uploads/files/24780573468.pdfIn PDF document text
    • https://mallorcaboom.com/res/wysiwyg/file/55311233610.pdfIn PDF document text
    • http://mathrainbow.com/userfiles/file/sewaw.pdfIn PDF document text
    • http://naphotelbangkok.com/userfiles/files/kuraparujemuvokarivori.pdfIn PDF document text
    • https://jakspravnenapsa.cz/userfiles/file/satenexodejeraposinulibew.pdfIn PDF document text
    • http://www.scsk12.org/policy/files/files/xilijutoka.pdfIn PDF document text
    • http://camelliafb.com/uploads/files/202109092059573095.pdfIn PDF document text
    • http://trevelci.ru/ckfinder/userfiles/files/93923535414.pdfIn PDF document text
    • https://desco.scp.hr/files/10937265900.pdfIn PDF document text
    • http://libron.pl/fckupload/assets/file/fosivuririjubotoko.pdfIn PDF document text
    • http://murasakijr.com/uploads/files/barenivoxotepuzipirupime.pdfIn PDF document text
    • http://easyhypermarket.com/userfiles/file/pejar.pdfIn PDF document text
    • http://devitohomesorlando.com/userfiles/files/fajodabumepi.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140ed3ca50df---pajosaguw.pdfIn PDF document text
    • http://heathrowairporttaxi.website/userfiles/file/56503078230.pdfIn PDF document text
    • http://zaiger.ru/img/file/nenawufexibomepesurobuvod.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dbce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBCE 11424 bytes
SHA-256: 54c41927e34d9d2450b6dd68dac76fdace8f4bd4e58ab0a44fe3b93e0bb789ad
font_01_sfnt_off0000f65e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF65E 18112 bytes
SHA-256: 5415beb4cf0537bb1c879e402fe5fbfca48c3ffe591af61da793a986cd9c8f7e
font_02_sfnt_off0001253f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1253F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1