Malicious PDF — malware analysis report

Static analysis result for SHA-256 cefc97873a04fe7e…

MALICIOUS

PDF

69.0 KB Created: 2021-09-21 06:57:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ee883a8e086e1338ae260f40d0c73783 SHA-1: 6394508e71701cfcfb735aea356fe2d1930c84d7 SHA-256: cefc97873a04fe7e96d6977dd60ee436ccf17d7b9d0814fff63089016de7dea4
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, many pointing to compromised WordPress installations and disposable hosting, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a common PDF-based lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://estoniapools.com/contents/files/pimipa.pdf
    • http://etalentlink.com/uploadfile/file///2021092109564441.pdf
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/63ecf5f0f18fee970271a88daf943bac/foxikutogawitakafeduja.pdf
    • https://drddvichitra.com/userfiles/file/63312312345.pdf
    • http://aeusjtu.pretty-match.com/upload/files/87236968279.pdf
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/121990c3a0e9f06a49ceea5c7d0a5f49/zotamo.pdf
    • http://baby-daycare.com/uploads/files/202109071213501624.pdf
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614885bf45903---mejagupososubon.pdf
    • http://zawodydrwali.pl/app/webroot/userfiles/file/fevufexusinetufuvosereba.pdf
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137fd65bb2fe---doxedodun.pdf
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ed92c3b297---levawoviz.pdf
    • http://violetstudio.in/userfiles/file/47986102796.pdf
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/afripfbqpjeeed36jluvg1d1iu/32669576597.pdf
    • https://aimtronu.org/userfiles/file/fedefifisunof.pdf
    • https://g-stampo.com/pics/pages/file/gimoxodofawisat.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/3ov47pkv65ecvfup519asi2r91/5107149746.pdf
    • http://sumisaedu.com/FileData/ckfinder/files/20210906_8CDB34A6E4DD41A7.pdf
    • http://quesnelfoundation.ca/userfiles/file/14068424208.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=java+activity+class
    • 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_off0000ae8e.bin
cf0e4759ee223f243fab8594f9a87fb283ff56745a34c34b23dca94a9b5c2680
pdf-font-stream PDF embedded font (sfnt) at offset 0xAE8E 16352 bytes
font_01_sfnt_off0000d894.bin
0aa33ad8cc3c9494c607b0c53a8b5e6c073a5610280c63444665044b72b0ac88
pdf-font-stream PDF embedded font (sfnt) at offset 0xD894 9936 bytes
font_02_sfnt_off0000eeb1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEB1 16792 bytes