Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5c6c2e4445fdd6d…

MALICIOUS

PDF

72.8 KB Created: 2021-09-09 11:27:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f4e64b99160546f5d414a448a504f40c SHA-1: 6f11b88adb6af125d4bbdd72f8830d3c06ca1b28 SHA-256: c5c6c2e4445fdd6dafeca15296b0772e38e77d1441b30044747bbc78b831b1e0
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to disposable domains, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing or malware distribution campaign, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://wastran.ru/uplcv?utm_term=miracast+android+tv+apk PDF link annotation
    • https://cuatudongsaigon.net/uploads/files/lafosubimabanapagibulusiz.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/60105770117.pdfIn PDF document text
    • http://osc-pribor.ru/products_pictures/file/nudupemilagekejajuzopami.pdfIn PDF document text
    • https://cuatudongsaigon.net/uploads/files/81977572.pdfIn PDF document text
    • http://shesob.com/file/files/56797517910.pdfIn PDF document text
    • http://www.liveartsaskatchewan.com/wp-content/plugins/formcraft/file-upload/server/content/files/161361050324be---97303205366.pdfIn PDF document text
    • http://toyotarent.kr/FileData/ckfinder/files/20210904_06F5D411BD2B88AD.pdfIn PDF document text
    • https://bselink.com/userfiles/file/pelagakuvakakepedikizirin.pdfIn PDF document text
    • https://auditorescr.com/ckfinder/userfiles/files/24782311027.pdfIn PDF document text
    • https://jetaime-shop.com/files/91675299171.pdfIn PDF document text
    • https://emprenderem.cl/files/gepugasafixemuvutijesu.pdfIn PDF document text
    • http://pfmconsulting.org/survey/userfiles/files/xawepilisu.pdfIn PDF document text
    • https://springkasteelhuren.be/userfiles/file/kegometonot.pdfIn PDF document text
    • https://jogamiskolc.hu/ckfinder/userfiles/files/nipamifutivatakubipu.pdfIn PDF document text
    • http://hkbroadwin.com/userfiles/98048301782.pdfIn PDF document text
    • http://tianlanlawyer.com/filespath/files/20210908172151.pdfIn PDF document text
    • http://jd6618.com/jd6618/file/2021-9/file/LwpCms2021_09_02_21_19_52_5955.pdfIn PDF document text
    • http://carlaschroyen.com/content_docs/97935606917.pdfIn PDF document text
    • http://angelofthewinds.net/ckfinder/userfiles/files/fatexovanidopajeraz.pdfIn PDF document text
    • http://kirche-treuen.de/UserFiles/File/19809909548.pdfIn PDF document text
    • https://a-guskov.ru/uploads/files/32449821152.pdfIn PDF document text
    • http://ambulatorioveterinariocigliano.com/userfiles/files/95734390256.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133e378abc36---11894270971.pdfIn PDF document text
    • http://osteriailgalloelinnamorata.com/userfiles/files/jezenixeveripurobosas.pdfIn PDF document text
    • https://tes-sys.com/uploads/ckfinder/files/20210909/16311307276540.pdfIn 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://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_off0000ba38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA38 16876 bytes
SHA-256: 60de0638cfc0ed897ed6ca9b0f27c5c375161c215a9bed4675f07f8c3ba928df
font_01_sfnt_off0000e5a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5A8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fdbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDBF 10480 bytes
SHA-256: 2e1784a5efdf266e1ef000667e612fe8278bdd3d6b4c7c569c371969564b369e