Malicious PDF — malware analysis report

Static analysis result for SHA-256 33497dfa2147312e…

MALICIOUS

PDF

79.0 KB Created: 2021-09-12 08:32:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: ab4c8c9a59d054f8e5d8f0efd595d5f4 SHA-1: b6bc5a860e998ad66e4fdc1e5cc7b99ec7ebfba3 SHA-256: 33497dfa2147312ef4ca48812b395fb96f00dcac3c2534638bd976909041b1d0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The presence of external URI heuristics and link farm indicators strongly supports a phishing or scamming attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://pistant.ru/uplcv?utm_term=disappointment+with+god+pdf+free+download PDF link annotation
    • https://hotelreviewreserve.com/basefile/hotelreviewreservecom/files/87626451200.pdfIn PDF document text
    • http://studioingegneriavaragnolo.com/userfiles/files/kogilekutasubowevago.pdfIn PDF document text
    • https://appvid.eus/userfiles/files/82065738840.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fedd8e1df2---23221261034.pdfIn PDF document text
    • http://hferrynetworks.com/FileData/ckfinder/files/20210904_DC442BE7464DD5EB.pdfIn PDF document text
    • http://elverum-revmatiker.no/images/file/nuwudegolukovivuf.pdfIn PDF document text
    • http://shengnabei.com/uploadfile/file///2021090901460954.pdfIn PDF document text
    • https://g55net.com/webpagebuilder/ckfinder/userfiles/files/vanoboveweluxudobimejipa.pdfIn PDF document text
    • https://olterus.info/contents/files/3494871591.pdfIn PDF document text
    • http://anapharmata.hu/ckfinder/core/connector/php/files/jedalitazuxevitovedago.pdfIn PDF document text
    • http://escuelasfutbol8.com/docs/files/15306772755.pdfIn PDF document text
    • http://mutitar.com/user_img/files/mifupu.pdfIn PDF document text
    • http://96stone.ru/userfiles/file/31711069311.pdfIn PDF document text
    • https://msvadba.ru/files/file/lobawuveluzopo.pdfIn PDF document text
    • https://itandem.net/ckfinder/userfiles/files/kivivujewatadi.pdfIn PDF document text
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/de3u9585uajj1cb04qhhp4r68d/wamof.pdfIn PDF document text
    • http://ct-tci.com/cttax/userfiles/files/90265400847.pdfIn PDF document text
    • https://sklepbonus.pl/userfiles/file/wegebefixizejesexuvu.pdfIn PDF document text
    • http://bassbasement.org/userfiles/file/52007652096.pdfIn PDF document text
    • http://radio-salsa.com/php/rs/filesupload/file/72387103059.pdfIn PDF document text
    • https://webmenuplus.com/images/file/25988325272.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136819b06071---56349416547.pdfIn PDF document text
    • http://www.ville-dammarie.com/ckfinder/userfiles/files/1471251642.pdfIn PDF document text
    • https://www.la-providence-ehpad.fr/ckfinder/userfiles/files/43489298369.pdfIn PDF document text
    • http://sten.kr/club/data/userfiles/file/20210909200017.pdfIn PDF document text
    • https://birudongker.com/contents/files/87751949754.pdfIn PDF document text
    • 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_off0000cbac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBAC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e3c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3C3 11032 bytes
SHA-256: 4d33a7a9099321e6d8a66141826cae89312996e1a838d5c9c2be503ffddeb7ac
font_02_sfnt_off0000fd0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD0D 18036 bytes
SHA-256: 61eeb097c69046919fbdff703dd671dac7ed6d0b0bae46b9e0256ee214b48f39