Malicious PDF — malware analysis report

Static analysis result for SHA-256 7bac8fba2d935456…

MALICIOUS

PDF

85.8 KB Created: 2021-09-04 20:59:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 20ab4f72093ad2036a8e00c048501959 SHA-1: 695cbcf413b79c20f73ca30616ce14d3a0a907cf SHA-256: 7bac8fba2d935456d7175adf74eddd78c95f770ba7540928765ffa77cfcba3ef
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Static analysis revealed it functions as a link farm, with numerous embedded URLs pointing to PDF files hosted on various domains, some of which are associated with compromised CMS uploads. The primary purpose appears to be SEO manipulation or distributing further malicious content through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://gloria-eurex.com/molefoku.pdf
    • http://akcjonariusz.com/UserFiles/file/munozunolajugiru.pdf
    • https://tepihtrava.rs//files/danekenaj.pdf
    • http://thebankcardservices.com/uploads/files/kenasasa.pdf
    • http://relocationservicesgroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076bd4d4dbe2---60007595031.pdf
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/0osinhugrtaiahufuo7o7fvm17/66462172149.pdf
    • https://aulacvn.com/upload/fck/file/54783710902.pdf
    • http://cadelupo.it/userfiles/files/segipoxudesedejanax.pdf
    • http://dishandspoonproductions.com/ckfinder/userfiles/files/12208297760.pdf
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/dbbe453230e4bc65ea42b29e6a324d50/divolemagupadipuzikiviv.pdf
    • http://iowatriallawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/27050645464.pdf
    • https://bulgariapools.com/contents//files/62636468781.pdf
    • http://xn--dlek-5qa.com/admin/UserFiles/file/xemowilivivif.pdf
    • http://www.vishalsahni.com/public/ckfinder/userfiles/files/durudodagidulefolenu.pdf
    • http://coyada.com/up_images/up_images/74746258453.pdf
    • http://stananddiane.com/clients/6/67/672a2699e369d648dd23e03de9deda78/File/58290319211.pdf
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/d5e9c3fcf4a549ec65df159810368e67/26122236774.pdf
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16073d4635f2f2---86944332029.pdf
    • http://ginzaramen.us/uploads/files/42517384127.pdf
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/7f69fb3feafd1adbf6b7d7ca828100de/fizinujigedunidiw.pdf
    • http://savitaco.com/uploads/images/files/85460412945.pdf
    • http://sushigonewildtogo.com/uploads/files/duxogabupifalavowubabobot.pdf
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4ae9b077d7---97350720660.pdf
    • https://autotrilogy.com/wp-content/plugins/super-forms/uploads/php/files/bc9b03419316463a149f9df08455a049/gawaxutomotoligaka.pdf
    • http://inoxbienhoa.com/upload/files/bulobuloferopar.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=petrology+the+study+of+igneous+sedimentary+and+metamorphic+rocks+pdf
    • 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_off0000e402.bin
e319b66720d3f22d1ccc3564c4a412d26a18cd2df14b2735f7e26c75a5f1bbbd
pdf-font-stream PDF embedded font (sfnt) at offset 0xE402 11376 bytes
font_01_sfnt_off0000fe75.bin
9a4e06173232d82fca484e87abbd7097521fb0672af43a50fd59252bf0f3d757
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE75 19304 bytes
font_02_sfnt_off00013078.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13078 16792 bytes