Malicious PDF — malware analysis report

Static analysis result for SHA-256 cece2ac029bb8eea…

MALICIOUS

PDF

72.9 KB Created: 2021-09-13 16:58:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 30270f0a276a16a56d3dd2c153b3055b SHA-1: 68759de4c86f2b825c1e3142d5bdd286f39fabd0 SHA-256: cece2ac029bb8eea59e2fd7b3e16b3a79209b67d3654f9cf2dc281678ac9c64e
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm. It contains numerous embedded URLs pointing to other PDF files hosted on a variety of domains, many of which appear to be disposable or of low reputation. This suggests a phishing or malware distribution campaign where the initial PDF serves as a lure to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://tonyprins.nl/images/uploads/file/vezutojisokilitoxepuzo.pdf In PDF document text
    • https://christianbelieversmatrimony.com/web/christiansbelieversmatrimony/photos/ckeditor/files/fuminujuvenil.pdfIn PDF document text
    • http://fleshlight-tw.com/userfiles/file/naluraven.pdfIn PDF document text
    • https://beytarimcilik.com/admin/editor_resim/file/66943038685.pdfIn PDF document text
    • http://detikakdeti.ru/img/file/51485861093.pdfIn PDF document text
    • https://komunalno-vrgorac.hr/files/jevogideteroz.pdfIn PDF document text
    • http://merklink.nl/site/data/ws/files/6480556847.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/3fh2rc1gluvksd9sgptak45oj5/mutenesopo.pdfIn PDF document text
    • http://crediramasrl.it/public/file/3055832945.pdfIn PDF document text
    • https://tigaintan.com/contents/files/53492596735.pdfIn PDF document text
    • https://easternresources.net/ckfinder/userfiles/files/44848374513.pdfIn PDF document text
    • http://energo-market.ru/sadm_files/42293533308.pdfIn PDF document text
    • https://confetti-seasons.ru/upload/files/xojeneradivomoxodunesife.pdfIn PDF document text
    • http://consulcongress.it/uploads/assets/file/povukuvades.pdfIn PDF document text
    • http://songhandiban.com/uploadfile/file/2021090513593173499.pdfIn PDF document text
    • https://hondamienbac.vn/userfiles/file/26965241380.pdfIn PDF document text
    • https://dialogueinpraxis.net/files/docs/gujerixugagamexusovetuver.pdfIn PDF document text
    • http://remont-etalon.ru/upload/files/88412067663.pdfIn PDF document text
    • http://bigyikesmedia.com/home/xtremweb/public_html/consultinstitute/web/upload/files/7218305339.pdfIn PDF document text
    • http://dalnoboy.org/data/filestorage/upload/files/wimofuliwelu.pdfIn PDF document text
    • https://shipnhanh247.vn/asset/files/jasuzaj.pdfIn PDF document text
    • http://kmjmt.com/news/upload/file/210905024645323631l6glhi.pdfIn PDF document text
    • https://carmelocuritiba.com.br/ckfinder/userfiles/files/61397445597.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=apk+bullet+echoPDF 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_off0000b835.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB835 18736 bytes
SHA-256: df897cb6aeaf0a0bad01f1abac7bf3bf2384388d68f65d69ec95d8d22c25d61e
font_01_sfnt_off0000e7e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7E5 10156 bytes
SHA-256: 47408cca7c9a53de42902bd7707c1aed53aaf1438ad094605ea5d037643f881e
font_02_sfnt_off0000fe95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE95 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1