Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8db20074c1b31ca…

MALICIOUS

PDF

71.6 KB Created: 2021-09-28 19:52:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 2701022630d6a0a4135d5349cd941679 SHA-1: 37cf92768c33ebad11ba14e61e75774416afde51 SHA-256: c8db20074c1b31cabb47ab36fc7c94fe621ffb8a87d5c9c5e74eb6b5483e5c1d
126 Risk Score

Malware Insights

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

The file is a PDF identified as malicious by ML classifiers and ClamAV. It contains numerous embedded URLs, many pointing to domains that appear to be part of a link farm, as indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic. The primary purpose seems to be directing users to potentially malicious or phishing content through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://restavratorstvo.com/ckfinder/userfiles/files/dipijufelavax.pdf In PDF document text
    • http://globalbando.com/DATA/upload/files/202109261411057330.pdfIn PDF document text
    • http://unipsyclinic.com/userfiles/file/20210909163205.pdfIn PDF document text
    • https://gbagencement.fr/uploads/file/zetixilerumudijoxopi.pdfIn PDF document text
    • http://objets.immoweiss.lu/userfiles/files/18497738852.pdfIn PDF document text
    • https://aeternoplanning.com/ckfinder/userfiles/files/73556387607.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/fadifulijezazekojaxo.pdfIn PDF document text
    • http://anindecor.pl/files/file/zotin.pdfIn PDF document text
    • http://aircond.md/upload_fck/file/gilib.pdfIn PDF document text
    • http://cleversystems.ru/userfiles/file/77252151158.pdfIn PDF document text
    • https://prosaison.fr/userfiles/files/23792003605.pdfIn PDF document text
    • http://nhakhoasaigonkimcuong.com/uploads/images/files/xevod.pdfIn PDF document text
    • http://eaupureinternational.com/userfiles/file/64688356300.pdfIn PDF document text
    • https://fertilizerproductionprocess.com/d/files/rupopivejo.pdfIn PDF document text
    • https://cakkue.com/contents/files/votibagufopuxakux.pdfIn PDF document text
    • http://chrisnoblelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/59820171720.pdfIn PDF document text
    • https://lasanisports.com/files/zejegulanonojanumotujej.pdfIn PDF document text
    • http://1mosref.ru/ckfinder/userfiles/files/18785898055.pdfIn PDF document text
    • http://detskaoptika.cz/ckfinder/userfiles/files/bifevusujetal.pdfIn PDF document text
    • http://sgd42.ru/userfiles/file/68864382707.pdfIn PDF document text
    • https://projectmine.hu/ckfinder/userfiles/files/17806214622.pdfIn PDF document text
    • https://ariaparvaz.com/basefile/ariaparvazcom/files/15355552848.pdfIn PDF document text
    • http://enovosti.info/ckfinder/userfiles/files/56987724074.pdfIn PDF document text
    • http://kinel-hunter.ru/upfiles/file/99958510466.pdfIn PDF document text
    • https://chuyennhakienvangvn.net/upload/files/14995651147.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=wangari+maathai+unbowed+pdfPDF 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_off0000b4d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4D1 16724 bytes
SHA-256: 29395cdf7e50f64933371da02f5f574d224f6c0ca0305ca0a3b68d444ef266df
font_01_sfnt_off0000df67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF67 11048 bytes
SHA-256: ca568ec307a35780ba67cc952cc095368b745b1cf2de893afa4f72cccef1c1c5
font_02_sfnt_off0000f887.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF887 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1