Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1fa5f6813bf9d1f…

MALICIOUS

PDF

84.9 KB Created: 2021-09-23 07:10:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e984e73808c98f9dadf56e3c4bb7a569 SHA-1: 806d006c12753c5cee0682d2d37b6eabce3258f9 SHA-256: f1fa5f6813bf9d1f74384285e993124d9335a7ce239cab935af0667dc7ad8483
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of external URIs and link farms, many hosted on disposable domains or compromised CMS uploads, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the nature of link farms in PDFs often involves JavaScript to facilitate redirection, hence the inclusion of T1059.007.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://crewmak.ru/uplcv?utm_term=rpg+games+multiplayer+free
    • http://jjburgerut.com/uploads/files/bilakipegupavabegisot.pdf
    • http://hpcad.pl/Upload/file/rapasunetivamubeligapax.pdf
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/1c3lo4ahc3utdlfupt74tij1r3/18919879231.pdf
    • https://cncunse.com/d/files/dizitosurafifaburudiruzuw.pdf
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/203520030d8ec8fab8c37b9151f4ff0b/repovirukexizegexiti.pdf
    • https://albertoangel.sinecsas.com/ckfinder/userfiles/files/lemawijupiguladoxinuzo.pdf
    • http://telecycling.org/files/file/32953650663.pdf
    • http://massarentearchitettura.com/userfiles/files/ratowisetut.pdf
    • http://bayernglobal.de/userVZ/file/kuvise.pdf
    • https://aquamedicasatumare.ro/ckfinder/userfiles/files/zujapirazino.pdf
    • http://sweet-sugar.de/images/uploadedimages/file/dirozitibokivakiveniporas.pdf
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/161427ff1d377a---90341485215.pdf
    • http://tianfonmm.com/d/files/rowexor.pdf
    • https://gadesign52.com/uploads/files/202109050856157580.pdf
    • http://luxmeterthai.com/ckfinder/userfiles/files/97520374573.pdf
    • https://newsale.linyn.mobi/upload/ckeditor/pages/files/98987890762.pdf
    • http://studio70.eu/userfiles/files/kapabinir.pdf
    • https://kaskad-74.ru/images/uploads/8486777834.pdf
    • https://rajaketiga.com/contents/files/57050865456.pdf
    • https://hargagila.com/uploads/image/files/rewujabupivujezatoze.pdf
    • https://cambodiaangkorhomestay.com/userfiles/file/nijodoxobikiduw.pdf
    • http://adirondackseafood.com/ckfinder/userfiles/files/vizibamaruzujedonukawedid.pdf
    • https://sooryasales.com/uploads/file/23698948473.pdf
    • http://sipzip.com/userfiles/file/80140749812.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e829.bin
f89932e72c72c35f2e2bd7ffc0cee98458b29e16fcb3e5f3ddea4cb1c9f58b30
pdf-font-stream PDF embedded font (sfnt) at offset 0xE829 17524 bytes
font_01_sfnt_off0001151d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1151D 16792 bytes
font_02_sfnt_off00012d34.bin
3f3dce83a474c7b1ff3edccddab216895107aff482be959e5b435ec0c6b77b13
pdf-font-stream PDF embedded font (sfnt) at offset 0x12D34 10736 bytes