Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d65660ea7bf6131…

MALICIOUS

PDF

71.6 KB Created: 2021-09-25 12:44:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 1af98109ebe816fb51b8274a85b20d42 SHA-1: 0db88f485df211cb071c8613b8c8f09233d22345 SHA-256: 8d65660ea7bf6131ffb1e5362cbe33c897f5ce32b8826e7dff1448fb2c203465
166 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many pointing to disposable hosting, suggesting a link farm or phishing lure. The presence of 'wkhtmltopdf' in the metadata and the 'SE_LOLBIN_RUN_COMMAND' heuristic suggest the PDF might be used to exploit vulnerabilities or redirect users to malicious sites, potentially for malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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://khamtribacninh.com/images/files/45380703771.pdf In PDF document text
    • http://cachnhietwin.com/luutru/files/soxoxavovenixezabesozuwi.pdfIn PDF document text
    • http://agro-norwa.pl/userfiles/file/juzujadafanaru.pdfIn PDF document text
    • http://soyaksiesta3.com/userfiles/file/18086440107.pdfIn PDF document text
    • http://faurerom.com/userfiles/file/jinezol.pdfIn PDF document text
    • http://cartopack.be/Images/file/riguzidatoguzi.pdfIn PDF document text
    • https://bluetact.com/locktactyuma/userfiles/file/degubegajeneruvedukafo.pdfIn PDF document text
    • http://kpotplace.com/uploads/files/jomegitavezi.pdfIn PDF document text
    • http://www.introspekta.si/ckfinder/ckeditor_uploaded_files/files/bexebajexeworadumexikom.pdfIn PDF document text
    • http://kietminhrivet.com/upload/files/87657657203.pdfIn PDF document text
    • http://canyonmeadows.org/userimages/lokobez.pdfIn PDF document text
    • http://danieldesignpro.com/userfiles/29005673664.pdfIn PDF document text
    • http://sieuthivatlieuhoanthien.com/upload/files/surawetivuwiwedox.pdfIn PDF document text
    • http://emploi.nat.tn/ckeditor/ckfinder/userfiles/files/rewizigiraxituwalijag.pdfIn PDF document text
    • http://www.addvanceo.info/userfiles/files/18114256675.pdfIn PDF document text
    • http://medianet2000.net/amm_prod/image_news_popup/file/84803604056.pdfIn PDF document text
    • http://kanoonkaraj.ir/dbmanager/filebank/htmlgallery/file///7360887906.pdfIn PDF document text
    • http://studioguatta.it/userfiles/files/fitejuxiselimam.pdfIn PDF document text
    • https://managedentalclinic.com/ckfinder/userfiles/files/xabukelufame.pdfIn PDF document text
    • https://texasbordervolunteers.org/userfiles/file/samekijubazoderimela.pdfIn PDF document text
    • http://qdcmd.com/data/files/jedoxikevovogimonumifu.pdfIn PDF document text
    • http://skisun.it/userfiles/files/22736559189.pdfIn PDF document text
    • http://cu-hinothai.com/ckfinder/userfiles/files/7236019172.pdfIn macro / runtime command snippet
    • http://softtox.com/new/userfiles/file/52571335765.pdfIn macro / runtime command snippet
    • http://dobrasekacka.cz/userfiles/file/telisixitaj.pdfIn PDF document text
    • https://duocvinhkim.com/userfiles/file/43140206005.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=call+of+duty+4+modern+warfare+remastered+free+downloadPDF 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_off0000b2d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2D6 17364 bytes
SHA-256: 1f321d35da27347d2d975b0ac9aaa84ee4325a62fd62793205c8b2062e0b2ed2
font_01_sfnt_off0000df05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF05 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f71c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF71C 10832 bytes
SHA-256: a9a6e2851505f7eb1d06013bc936e79546d35503519cb4c05dabe5f8eed13d27