Malicious PDF — malware analysis report

Static analysis result for SHA-256 79916eccacc2b137…

MALICIOUS

PDF

85.3 KB Created: 2021-09-17 09:43:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f2dea43a1ad54b64d46a69ecf4bbe40f SHA-1: 3e94283e164f7f87469987b85d464a8d3bfb133a SHA-256: 79916eccacc2b1375b40896a10d9e653eeee75fd72b562729c4a0f02cf294f10
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress upload storage locations. The presence of numerous unknown URLs suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/161353fded0d86---velapibekukusi.pdf In PDF document text
    • http://mishor-uvk.com/uploads/files/davusuji.pdfIn PDF document text
    • http://plymouth-logs.co.uk/ckfinder/userfiles/files/sewumexenezamukumes.pdfIn PDF document text
    • http://zzquansu.cn/d/files/wegozozigagid.pdfIn PDF document text
    • https://zibarajabi.com/cache/fck_files/file/90973316797.pdfIn PDF document text
    • http://eros-arena.de/eros/userfiles/file/funojaf.pdfIn PDF document text
    • https://prettygreekvillas.com/admin/fckeditor/editor/filemanager/connectofile/47407045026.pdfIn PDF document text
    • https://certifiedcollisionrepair.com/home/cert/public_html/ckfinder/userfiles/files/59110559344.pdfIn PDF document text
    • http://nexxosrealty.com/userfiles/files/nizokan.pdfIn PDF document text
    • http://mecateengenharia.com.br/ckfinder/userfiles/files/64505794732.pdfIn PDF document text
    • http://exms.fr/sites/default/files/file/reminivunemasesuker.pdfIn PDF document text
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/16138fe22bb455---76549666333.pdfIn PDF document text
    • http://jtg-antracyt.pl/files/file/94566133533.pdfIn PDF document text
    • http://cbcom.fr/ressource/site-image/files/16629994068.pdfIn PDF document text
    • http://eatatrudy.com/uploads/files/7017599138.pdfIn PDF document text
    • http://rent2day.ca/ci2/userfiles/files/41553624848.pdfIn PDF document text
    • https://kangaroovietuc.vn/webroot/img/files/pumidetadeguwe.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/161394b781963c---8773714521.pdfIn PDF document text
    • http://dribblebar.pl/userfiles/file/6424559131.pdfIn PDF document text
    • http://pho32shabu.com/uploads/files/pijid.pdfIn PDF document text
    • https://rzfmuhasebe.com/userfiles/file/mixixilubivizixulal.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/4f4fdb1cea0879b99c11d4e85307835b/vufaroxinabozejezeviwox.pdfIn PDF document text
    • http://hmed.vn/upload/files/26770898553.pdfIn PDF document text
    • http://brucemayrockinstitute.com/assets/ckfinder/core/connector/php/uploads/files/mekuvif.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=android+9+ps4+controllerPDF 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_off0000e954.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE954 17916 bytes
SHA-256: 316dec07068ff25fcec3bfb0651800b90f364b5592998e6066d0306b2e52a47b
font_01_sfnt_off00011792.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11792 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012fa9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FA9 10572 bytes
SHA-256: d3b86a79edb0d8be439d004bae432f22487ac156a3198b2a18390ffbebe20145