Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6ecc16591ee879b…

MALICIOUS

PDF

95.0 KB Created: 2021-09-18 13:12:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ba872e8faf8b7db983f9fcbd1defe444 SHA-1: ad9e447c62d47d762318e617aaff2d3f200fbfd2 SHA-256: b6ecc16591ee879b04174a1062e58ee3f64430fa139309e3c86c266915a29bc0
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the link farm heuristics and URL analysis.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://adabaskimerkezi.com/upload/file/seniwubob.pdf
    • http://museodegliarazzimarsala.com/userfiles/files/28459847067.pdf
    • http://banner-ever.com/ckImg/files/nifedofakugirow.pdf
    • http://immobilieninvestors.net/userfiles/file/3540070875.pdf
    • http://ttfi.org/app/webroot/userfiles/file/mavafunoxidekef.pdf
    • https://barrierball.cl/ckfinder/userfiles/files/86943451155.pdf
    • https://latrinquette.com/upload/editor/file/tubuwupukavasug.pdf
    • http://naturenhuman.com/app/webroot/userfiles/file/jokojob.pdf
    • https://kungfuclasshongkong.com/louis/taichi/ckfinder/userfiles/files/wararubigosulubidudek.pdf
    • http://canxetaianhduc.com/images/file/retow.pdf
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/235d9b7ab470180bff7ddd2c47f5c7da/xafexaritepabavaviduku.pdf
    • http://texinpack.com/uploadfile/file///2021091104415355.pdf
    • http://themetamorphoseprogram.com/userfiles/file/xebegujijevetiledi.pdf
    • https://okna-kursk.ru/page_edit/_samples/userfiles/files/tulibolevur.pdf
    • http://alconsprom.ru/ckfinder/userfiles/files/34091255945.pdf
    • http://www.moyekolodin.com/files/mapusu.pdf
    • http://mdcegy.com/app/webroot/img/fck/file/vulujelusegef.pdf
    • https://satnamunicipalcorporation.com/admin/ckfinder/userfiles/files/sesuluwuroboxobarikode.pdf
    • https://hobbypet.cz/files/file/41297907954.pdf
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/21c1aa47c03a5796a1329aca76c223f8/robebazo.pdf
    • http://capitaldanceacademy.com/userfiles/files/64610901656.pdf
    • http://vet-arrighicolangelicristilli.eu/userfiles/files/tuzobirogawusekijiber.pdf
    • http://pegastelco.com/pictures/files/23880088059.pdf
    • https://telechips.com/ckfinder/userfiles/files/19495875050.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ff5b79ece9---lasikogi.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=dance+moms+putlocker
    • 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_off00010f04.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F04 16792 bytes
font_01_sfnt_off00012716.bin
b09ed975ff1654afa1b208b4efbae55019a2c9f5094feb72ec9fefdd6ac7b137
pdf-font-stream PDF embedded font (sfnt) at offset 0x12716 18144 bytes
font_02_sfnt_off000155d1.bin
ac3382d5b5326727dacc491e06a2d612e754a3c9c75dac3c38d1299a9564330f
pdf-font-stream PDF embedded font (sfnt) at offset 0x155D1 10636 bytes