Malicious PDF — malware analysis report

Static analysis result for SHA-256 a983c9380b64f20e…

MALICIOUS

PDF

70.1 KB Created: 2021-10-03 05:57:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 5733e009511e8c1e5fb6723cfcdc63c0 SHA-1: 926070c12e40289356233943d4d713ced5c617d0 SHA-256: a983c9380b64f20edec1aadf5f3635c39da8f71b88071fb92a28c1e8f958a617
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection for a phishing trojan. It functions as a link farm, with numerous embedded URLs pointing to external sites, some of which are hosted on compromised WordPress installations. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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 http://elektro-galerie-hamburg.de/userfiles/file/97025189169.pdf In PDF document text
    • http://bukvoznaika.ru/ckfinder/userfiles/files/lugewejusaxesukatumesik.pdfIn PDF document text
    • http://kortennis.co.kr/B/ck/ckfinder/userfiles/files/28452670873.pdfIn PDF document text
    • http://vipacademy.org/userfiles/file/595210121.pdfIn PDF document text
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614256e92d638---90219321941.pdfIn PDF document text
    • http://www.siphonicflowmandiri.com/upload/files/71662983078.pdfIn PDF document text
    • http://theclelandgroup.com/img/upload/file/32048429923.pdfIn PDF document text
    • http://qunjl.com/userfiles/files/69058301682.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133c2278d326---pegigizobuxozovupunewire.pdfIn PDF document text
    • http://utcsp.rustyramone.com/uploads/files/xipumapiligugixovalud.pdfIn PDF document text
    • http://dirpub.org/editor/ckfinder/userfiles/files/56562289987.pdfIn PDF document text
    • http://osteriailgalloelinnamorata.com/userfiles/files/xakero.pdfIn PDF document text
    • http://www.hermosabeachbungalows.com/userfiles/files/5391140924.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/cb35fbe32475fee099e67a0d3a3dfddd/wososufileziwipejojobogot.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613fb3664fabf---regewudutonabagupit.pdfIn PDF document text
    • http://blessingsngo.in/userfiles/files/sirezaxuvik.pdfIn PDF document text
    • https://jsptti.com/ckeditor/ckfinder/userfiles/files/78011531592.pdfIn PDF document text
    • http://leaders-adv.net/userfiles/file/6576062307.pdfIn PDF document text
    • http://rydelko.eu/userfiles/file/xujogowa.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/9c894257eeae208ec3109c52240dcb6e/60181181610.pdfIn PDF document text
    • https://feltshoe.com/userfiles/file/45871599597.pdfIn PDF document text
    • https://inprovitmexico.com/ckfinder/userfiles/files/64545529550.pdfIn PDF document text
    • https://torgradio.ru/new/files/file/lewosowujamipasanezotogo.pdfIn PDF document text
    • https://vipbeachhouse.com/uploads/editor/file/76268601768.pdfIn PDF document text
    • http://lorofilmes.com/Uploads/ckfinder/userfiles/files/18738847710.pdfIn PDF document text
    • http://babyshelter.net/assets/upload/files/felaxonenibaxek.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=epidural+anesthesia+is+injected+into+thePDF link annotation
    • 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_off0000b333.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB333 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB45 15352 bytes
SHA-256: b4a60dd1bde21585177e88259131ef1e163b9ae5ad82663d30c5b1a34ea3dac8
font_02_sfnt_off0000f1b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1B0 10824 bytes
SHA-256: a84c5c1dac9084a03318964f53ca1ec4521ae00e872166e9dc77b1166ac71d1c