Malicious PDF — malware analysis report

Static analysis result for SHA-256 37de36ae37719c45…

MALICIOUS

PDF

88.4 KB Created: 2021-07-18 13:11:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: f27145634427147e891f880a89aedfd3 SHA-1: 28b369f50a10b647a1af1f109f37fc7216eaa15e SHA-256: 37de36ae37719c454ee6b51fe66f500c22df36ea6914a60a053217bbb8b78407
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 disposable domains, indicating a link farm designed to distribute malicious content or phish users. ClamAV detected this as Pdf.Phishing.Trojan, and ML classifiers also flagged it as malicious. The presence of external URIs and link farms suggests an attempt to lure users to malicious sites, likely as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://xn--l3cbpp3gh4a5g5c.com/userfiles/files/rixam.pdf In PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609dcf3c031ea---guluzobiworelemumebilil.pdfIn PDF document text
    • http://ajivikafinance.com/userfiles/file/duxejuwegumonuv.pdfIn PDF document text
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/e43c0dd08e6c391c5e5af585c87776d0/74829648590.pdfIn PDF document text
    • http://www.mbk-montage.nl/ckfinder/userfiles/files/jovidukuvutibonagomofar.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/160cab4f2af42e---27640278798.pdfIn PDF document text
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/8sp9dpbjv2s840m9n5iugeqp81/nurudovarejumiweroneli.pdfIn PDF document text
    • http://www.mezmat.ru/ckfinder/userfiles/files/55748396706.pdfIn PDF document text
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a7d2055f0e---xapalegakebutomakur.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/a8e58989102a91e65950af982a5b9d32/83956782258.pdfIn PDF document text
    • http://longthinhphat.net/uploads/files/92883533223.pdfIn PDF document text
    • http://araonline.hu/uploads/file/85625503979.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607338c6b51f8---66892203093.pdfIn PDF document text
    • https://universal4shipping.net/userfiles/file/54418015901.pdfIn PDF document text
    • http://sbnjl.com/userfiles/files/xagatovalafakabedopek.pdfIn PDF document text
    • http://candybeauty.vn/upload/files/nanojasefewegobawemupu.pdfIn PDF document text
    • http://abnicum.com/files/file/zogabulag.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/160dbd26bb845a---fawurazo.pdfIn PDF document text
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/f7fd89c2595cbd0d8452b3350bbe63db/lidonegalojerux.pdfIn PDF document text
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607238d99a459---65444697025.pdfIn PDF document text
    • http://xycrusher.com/d/files/45384775310.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/rcfk4njmr9uqkrktkh7jgl268n/83253760563.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/b6a077e216833c77660ddfb4351fc1d3/26716258410.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c005bbe84fa---66634072159.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=scary+movies+to+watch+for+freePDF 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_off0000f725.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF725 10792 bytes
SHA-256: fb4fe0985011b8d47e49f95f633716931c9991982bc622e7ae58fae30bff19a4
font_01_sfnt_off0001101b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1101B 16952 bytes
SHA-256: fefc80a46c96daff8600d7660cba511182b0a18fe48318dc76e8e6f434cc1b61
font_02_sfnt_off00013c4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C4D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1