Malicious PDF — malware analysis report

Static analysis result for SHA-256 852c9fe0bd90f54d…

MALICIOUS

PDF

76.1 KB Created: 2021-08-08 03:11:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d2b96b971ec8b82e5fb241ce5d0edb4f SHA-1: 41af4a35c31a10f24ee2677f9b100ce6247ecb72 SHA-256: 852c9fe0bd90f54de2affdea77593051f9677259c539a901eb2a9a5b06d64896
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was identified as malicious by ClamAV and an ML classifier. It functions as a link farm, containing numerous URLs that point to compromised CMS upload directories. These links likely serve as lures for phishing attacks or to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://irlanc.ru/uplcv?utm_term=fundamentos+de+econom%C3%ADa+jos%C3%A9+silvestre+m%C3%A9ndez+pdf+gratis PDF link annotation
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/h23medlqcvdah4jaqmcm217vii/xuwiligo.pdfIn PDF document text
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/97749fe4d2805f8c0a80714f87d14cb2/69480398526.pdfIn PDF document text
    • http://n2nnetworks.com/files/others/86586963712.pdfIn PDF document text
    • http://wtmongolia.com/materials/file/papofekulobebagewemugot.pdfIn PDF document text
    • http://elitaliaweb.it/upload/file/8748333022.pdfIn PDF document text
    • https://www.almuhja.com/ckfinder/userfiles/files/71848386535.pdfIn PDF document text
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/160819da92a7d8---48382111669.pdfIn PDF document text
    • https://agatanorek.com/files/file/83198131486.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16081f47d49025---46152432633.pdfIn PDF document text
    • http://e-kva.ru/admin/ckfinder/userfiles/files/12230367017.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca28cf0a68---16885625862.pdfIn PDF document text
    • https://svetpoznaniyaonline.ru/wp-content/plugins/super-forms/uploads/php/files/548848ad86f6cd60fb11564e2c645327/8054014151.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/02ndg2edc83486q6dqg1dichg3/2087405119.pdfIn PDF document text
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/0594b1f22eb39b41785d0e8792e587d9/domejiwotupawun.pdfIn PDF document text
    • https://www.vbclighting.com/wp-content/plugins/super-forms/uploads/php/files/83a048a7d9d030083ab0729315237ef0/bujawopiwoso.pdfIn PDF document text
    • http://ed-web.cz/userfilesfile/75513214163.pdfIn PDF document text
    • https://incoyun.com/calisma2/files/uploads/70098334248.pdfIn PDF document text
    • http://entryexpress.online/chapter_images/files/gilupadetukulir.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/a2a886210445dd8ba24436099a2c4371/56135977003.pdfIn PDF document text
    • http://hzdsbg.com/uploadfile/1621426727.pdfIn PDF document text
    • https://journeywithmypet.com/ckfinder/userfiles/files/19262597222.pdfIn PDF document text
    • http://ankaraeksioglu.com/resimler/files/26442388273.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_off0000c21e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC21E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000da35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA35 11512 bytes
SHA-256: 6469797dbd49e900ca672493440b15238d504fad5becbf65daf17b05e2fe7fb4
font_02_sfnt_off0000f4e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4E9 16808 bytes
SHA-256: ea9635f3b51547e2a9f90db44dc7e5069cef758d29745319214ba762fbd1a735