Malicious PDF — malware analysis report

Static analysis result for SHA-256 6740313bac7a8370…

MALICIOUS

PDF

67.4 KB Created: 2021-09-27 11:35:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 6f7a74d5b7099e57b4fccee2a6a58165 SHA-1: 866119e257254310c619356aeb71de8fc863dc0d SHA-256: 6740313bac7a8370cc7e7eeef4e90854bd4b7cf49b17eeb6227c424d54220660
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous external URIs and links to compromised CMS upload storage, suggesting it's part of a link farm designed to redirect users to malicious sites. The file's structure and the presence of multiple links point towards an attempt to manipulate search engine rankings or distribute malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://archism.ru/uplcv?utm_term=cheap+rank+tracker PDF link annotation
    • http://videotour24.com/data/fckupload/file/vonegukajufasadijowapete.pdfIn PDF document text
    • http://lexxyin.net/files/fckeditor/file/lezapiwalixama.pdfIn PDF document text
    • http://altronic.pl/!mag2011/userfiles/file/72102662915.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613e91d82872b---nidaxemudi.pdfIn PDF document text
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/tqdh7rbpk266vd45o5ad1smho1/lokodirevidaji.pdfIn PDF document text
    • http://turatabor.hu/media/kanakubedikesogaligatozin.pdfIn PDF document text
    • https://home-consult.lu/userfiles/files/tiwom.pdfIn PDF document text
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142138e386e1---29333871164.pdfIn PDF document text
    • https://jaukiaplinka.lt/ckfinder/userfiles/files/89032948612.pdfIn PDF document text
    • https://tennis94.fr/img/pics/files/xumarediwad.pdfIn PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614166b5c3e4f---tuminemo.pdfIn PDF document text
    • http://silverspringabw.com/uploads/files/92085859129.pdfIn PDF document text
    • http://yarpb.ru/pic/userfile/bezutewawukid.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614520c92f444---tutipetek.pdfIn PDF document text
    • http://zezoalza.com/ckupload/files/nitukitazedudusewute.pdfIn PDF document text
    • http://ap116.ru/userfiles/file/67435952958.pdfIn PDF document text
    • https://thaiahpa.com/flash/files/73076323587.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/tmeu4rkrpjkrcm2fpq4l7d303b/51573864220.pdfIn PDF document text
    • http://www.phuongdonggolf.vn/app/webroot/uploads/files/menunuwugedalumaveguvesun.pdfIn PDF document text
    • http://ristoranteibucanieri.it/userfiles/files/80177502827.pdfIn PDF document text
    • https://mauspro.net/upload/files/jolupezezexukojatob.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_off0000ac10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAC10 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c427.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC427 10168 bytes
SHA-256: cfe1b5ac130193ecd531111f597f1ec3467405386a506822b5bd909406de5755
font_02_sfnt_off0000dae8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAE8 14488 bytes
SHA-256: 9094731f5516fb0ea5875d63e844dd28960d0f702c239b514a799271ff5c5a9b