Malicious PDF — malware analysis report

Static analysis result for SHA-256 2557e3a2311548ef…

MALICIOUS

PDF

76.5 KB Created: 2021-06-20 15:34:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 572840aa925b2342e6c28bba08b51b2c SHA-1: 26300474ff16ef25876c2a250bf5151857a54933 SHA-256: 2557e3a2311548ef72b75c501a80f1bf7c8cdae46bd5ddba9dc990649e1829a3
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to compromised WordPress upload storage locations, likely to download further malicious content. The document body, though heavily obfuscated, contains references to 'einaudi sheet music free download', suggesting a lure to entice users to click on the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607783c4751c6---wurajebonopuni.pdf In PDF document text
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/55130518952.pdfIn PDF document text
    • http://cloverpark1960.com/clients/1/17/17c242f0968dc4bce059666b43fbd075/File/mofodabijodibu.pdfIn PDF document text
    • http://starlightcelebre.org/clients/4/43/43e9139217482d7666ce300faf566241/File/jobivunidado.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609661d9e6dfa---voroporada.pdfIn PDF document text
    • http://karpatskiles.ru/store/file/zavumodetubigo.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/59f00c9143804bdc7e82a7f837667f04/xejidowudepopemumovene.pdfIn PDF document text
    • http://bioterapiazabiegi.pl/obrazy/file/857582116.pdfIn PDF document text
    • http://sun-green.be/ckfinder/userfiles/files/newurewin.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5be0985482---daferejinijetudemizilo.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/nopet.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b56223c235---47835305993.pdfIn PDF document text
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/4d9ee28166e512bc1ece46aa52693f13/59686220917.pdfIn PDF document text
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1609a7648a1d79---80849183556.pdfIn PDF document text
    • https://implant-drill.com/userfiles/file/92143171239.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/021f2b1929f7b2713fa88e7a3b3daac1/fewakomebuvod.pdfIn PDF document text
    • https://gagiongvitgiong.com/ckfinder/userfiles/files/mefejarag.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160779b3da7971---tidomibilunafimusibiw.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=einaudi+sheet+music+free+downloadPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC96 5312 bytes
SHA-256: c712d25eda3d2fe121eb39452f1a2fd7a8d4e02f629819c73878b28fcad16049
font_01_sfnt_off0000fe92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE92 10656 bytes
SHA-256: 0a99f80e9d5c094faf75e050a66302f98d67df2df8001396f867e9d3372cc0c3