Malicious PDF — malware analysis report

Static analysis result for SHA-256 5441a8c352b1b93f…

MALICIOUS

PDF

83.4 KB Created: 2021-09-12 07:11:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: acb20a51e5de3a16bf2806ce23f591ea SHA-1: 7330f9f3211665c76d9e7cba1725f43f1a6b974b SHA-256: 5441a8c352b1b93f548bdfe2ea3554e040be4827a59f8dbc2818eef3ea56d594
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm for SEO poisoning or phishing. The ML classifier and ClamAV detection strongly suggest malicious intent. No scripts were extracted, but the structure and embedded URLs point towards a malicious document designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://www.enfersalus.com/ckfinder/userfiles/files/98165975605.pdf In PDF document text
    • https://larustt.com/upload/ckfinder/files/bepedigikerunepot.pdfIn PDF document text
    • https://manenshop.com/upload/files/siwuretik.pdfIn PDF document text
    • http://bidadapatidar.com/userfiles/file/83654097219.pdfIn PDF document text
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/a0ii98fq6d7qp8u934ms2e7qm0/95415760942.pdfIn PDF document text
    • http://appinaris.net/ckfinder/userfiles/publics/files/sejorik.pdfIn PDF document text
    • http://kingkady.com/uploadfile/files/funezip.pdfIn PDF document text
    • https://floresdeserrezuela.com/aym_image/files/85527032625.pdfIn PDF document text
    • https://rallstarawards.us/nbloom/fckuploads/file/vewatovelawu.pdfIn PDF document text
    • http://hbaoge.com/upload/files/tijunufiteriwefawi.pdfIn PDF document text
    • https://coolinterier.sk/upload/files/81245525287.pdfIn PDF document text
    • http://nataliashishkina.com/userfiles/file/sijavalafigeg.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/tutes.pdfIn PDF document text
    • http://rem-stroymont.ru/img/file/81586059227.pdfIn PDF document text
    • https://ibextrail.com/editor-images/piretur.pdfIn PDF document text
    • http://kiemdinhcan.com/Images_upload/files/23230167579.pdfIn PDF document text
    • https://lochoanggia.com/upload/files/86322339152.pdfIn PDF document text
    • http://yesilderecine.com/admin/editor_resim/file/10872515660.pdfIn PDF document text
    • http://baldonimarcostudio.eu/userfiles/files/dodipepujujapu.pdfIn PDF document text
    • http://edilgroupdigiovanni.it/userfiles/files/roxizepowodugizowiki.pdfIn PDF document text
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/161394cc532326---74744044041.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/80c431a122faa836f32a2b6b46620a52/koropijabavan.pdfIn PDF document text
    • https://trungtamgiasuhcmmq.com/uplaod/quangtri/files/52479711797.pdfIn PDF document text
    • https://taxfirma.com/userfiles/file/bexipuzoxupuwedaru.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=autentico+3+textbook+answersPDF link annotation
    • 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_off0000da55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA55 10852 bytes
SHA-256: b0a72a6a600dc12105626947d7a536af202a279d1a10c208e7408d87c97d8807
font_01_sfnt_off0000f3bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3BD 19936 bytes
SHA-256: 033e06f18ee714d03beec017d7345c038407144aa934e241b44a387acdf241f2
font_02_sfnt_off000127fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127FD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1