Malicious PDF — malware analysis report

Static analysis result for SHA-256 88b25fc1f98947e5…

MALICIOUS

PDF

123.1 KB Created: 2021-06-14 20:36:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 3b4c7dc9e94584a1d51dbf5a293bc02e SHA-1: 5e8b78541c36038023d4ff07a7b981cf36c5c8b2 SHA-256: 88b25fc1f98947e587f14dbc504e08c97ec48107953613a09ec137710fa3c887
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 https://crewmak.ru/uplcv?utm_term=smash+ultimate+best+characters PDF link annotation
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1047a59cf0---rejariwoloderenotazub.pdfIn PDF document text
    • http://coffee33.ru/archive/file/92244382835.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/17970138542.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1607137823637b---nugitefi.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/160830811e8c8a---meregema.pdfIn PDF document text
    • http://am-assets.com/aom/magnolia/userfiles/file/78700949183.pdfIn PDF document text
    • https://saatyapi.com/upload/ckfinder/files/jesuzaxupi.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/gsqe9903ab7inmcb1ibra2vs05/nukukonaxupenafulaz.pdfIn PDF document text
    • http://lifemartrealestateconnect.com/wp-content/plugins/super-forms/uploads/php/files/1vctduv2kqgdsvdtgid1sdeqp5/16266800169.pdfIn PDF document text
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/b8b6d7dd6e6a0434197606894c091a9e/33538872509.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608aa42fe6642---375445776.pdfIn PDF document text
    • http://berallebags.com/UploadFiles/FCKeditor/20210525163008.pdfIn PDF document text
    • https://aplusadvance.com/naver_editor/data/file/11401654879.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/d1d7f204964536a3f0a11a3b7ed5cfee/gawoxuxusogerowuf.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/fb3e1f7f816a8cd33bcb0fc0ab686458/23473812578.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00016e80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16E80 10920 bytes
SHA-256: 5b1c569182d5c2aaed5df95c63a33fab2dc5e833b68ef65302a78e7ac1520434
font_01_sfnt_off00019255.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19255 5284 bytes
SHA-256: f190183fc71faf762ec4963208267c456c498fe9574fec733c056d4689715556
font_02_sfnt_off0001a414.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A414 4892 bytes
SHA-256: 3831d0daf1ebf0b2aa4b3c907a77008cc03ebd869ac261e1c6ce6c55465fdab3
font_03_sfnt_off0001b5be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B5BE 12384 bytes
SHA-256: 1572fe8bc670a4a4decd4b0a9b80d94f9e456441ba906aa38b50d0c8f2abd4e2