Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9bd75abb3676d47…

MALICIOUS

PDF

79.5 KB Created: 2021-09-18 09:08:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 07d064a0a38a20b624e63d251a21c694 SHA-1: 5c15215ec7ca6bc8b5154033f95c54cf61f38728 SHA-256: d9bd75abb3676d479ce828f58e3bc3800e43acd55ebe923c0b6a7c52d6384654
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF file flagged by ClamAV as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to various external URLs, some hosted on compromised WordPress sites. The ML classifier strongly supports the malicious verdict. The primary attack pattern involves tricking users into clicking links that likely lead to further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://infrive.ru/uplcv?utm_term=old+messenger+version+apk PDF link annotation
    • https://aqua2go.pl/galeria/file/94055885859.pdfIn PDF document text
    • http://xn--80aafbladvtgxneccoge3bt.xn--p1ai/pict/file/50913375984.pdfIn PDF document text
    • http://pascalparrot.com/uploads/assets/file/31102730230.pdfIn PDF document text
    • http://master-stroi76.ru/userfiles/file/26280888298.pdfIn PDF document text
    • https://www.stock2morrow.com/ckfinder/userfiles/files/zotufepudipetaxurutuzadak.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137227621337---73460409689.pdfIn PDF document text
    • https://riolospettacoli.it/filesUploads/file/kudepijebapatefovogip.pdfIn PDF document text
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16131434551f61---55716314851.pdfIn PDF document text
    • https://mariellatriolo.it/public/file/60130692028.pdfIn PDF document text
    • http://alpanelektrik.com/depo/sayfaresim/file/5171219727.pdfIn PDF document text
    • http://fortwashington.abwingsmd.com/uploads/files/26806077392.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613921f52d036---33479658291.pdfIn PDF document text
    • http://alhouti.com/userfiles/file/21374816583.pdfIn PDF document text
    • http://nexxosrealty.com/userfiles/files/83841746858.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132d322aed68---36801722120.pdfIn PDF document text
    • http://come2menorca.com/images/file/90493957175.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/7630c5a540c67541d5962eb039f49feb/najolovapukuxujikakuj.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/33c805bf7f052e494578d72511f30c9d/fujipes.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144b441364f7---50168434766.pdfIn PDF document text
    • http://hanasushipickup.com/uploads/files/pazubimofonut.pdfIn PDF document text
    • http://wksystems.net/HotelEstimator/userfiles/file/vodeko.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_off0000d611.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD611 16384 bytes
SHA-256: bdf7d01021a785b4201a247d698d5fd2ed59b4941ccfe8f9d8eb33937849f869
font_01_sfnt_off00010021.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10021 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011838.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11838 10820 bytes
SHA-256: a7fc300cad2b123a6e59ba71702727614cedd48575c97d30cc295b51affb68a0