Malicious PDF — malware analysis report

Static analysis result for SHA-256 1576ecf4a1efedde…

MALICIOUS

PDF

71.6 KB Created: 2021-09-18 22:25:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 544f4ffd73663cb31db6646432a7a6ff SHA-1: 5c85da7b0e73d431fec30d5e18c79c8047bb52b3 SHA-256: 1576ecf4a1efedde258c82cf11748adb2d4215b45bada6c5e4d2649745cfc8f7
126 Risk Score

Malware Insights

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

The sample was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs pointing to PDFs hosted on what appears to be a link farm, a common technique for distributing malicious content or conducting phishing. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically indicates a non-clustered link farm on disposable hosting, reinforcing the malicious intent.

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 https://skatrip.com/basefile/skatripcom/files/dudonobazutolenaxatoke.pdf In PDF document text
    • http://ajisushionline.com/uploads/files/79930629474.pdfIn PDF document text
    • http://preiswerte-unterkunft-papenburg.de/mediapool/19884947998.pdfIn PDF document text
    • http://umffz21.ru/admin/ckfinder/userfiles/files/pumoxuguk.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16141d02de4768---binukodewuj.pdfIn PDF document text
    • http://dansungsala.com/uploads/files/nawulibeveze.pdfIn PDF document text
    • http://xn--hh0b97d8is16e.com/userData/board/file/fafilofevirab.pdfIn PDF document text
    • https://www.premiumtrade.ro/ckfinder/userfiles/files/zuwokimukixajuzuwatizag.pdfIn PDF document text
    • http://baschin-heizung.com/meineBilderAlbertGrundschule/file/87830419735.pdfIn PDF document text
    • http://verkaufs-akademie.com/userfiles/file/41745752272.pdfIn PDF document text
    • http://axwelindia.com/uploads/73684137539.pdfIn PDF document text
    • https://warsztatgdynia.pl/app/webroot/media/files/38945939859.pdfIn PDF document text
    • http://arablift.net/userfiles/file/didiluseb.pdfIn PDF document text
    • http://tribo.kz/userfiles/File/67314561049.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/9o0ioco3s479rghc91i5a69t52/41792730251.pdfIn PDF document text
    • https://sacc-la-chaux-de-fonds.ch/fichiers/file/24804227440.pdfIn PDF document text
    • https://www.cylinder96.ru/admin/ckfinder/userfiles/files/tafuzijewipogezo.pdfIn PDF document text
    • http://celyroknaterase.sk/editor_uploads/system/files/dozevexi.pdfIn PDF document text
    • http://veterinariomauracotti.it/userfiles/files/57496400191.pdfIn PDF document text
    • http://drairtools.com/ckfinder/userfiles/files/xupakitikivejafaj.pdfIn PDF document text
    • https://armature.ir/cache/fck_files/file/jarejam.pdfIn PDF document text
    • https://gemma.lucien-sv.info/uploads/files/6141b3ce301d1.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=persona+4+golden+quest+16PDF link annotation
    • http://s292376414.onlinehome.fr/datas/imgmail/file/88378596005.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_off0000b38a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB38A 17528 bytes
SHA-256: 97119d378e224699c0ce0406ef60fdccfc856435de44f673ea20f9f4f9296dec
font_01_sfnt_off0000e091.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE091 10876 bytes
SHA-256: 58110430413ccd50e9f6580f0eb5ba725d73ba9ff614df9c43d768e8afa18456
font_02_sfnt_off0000f976.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF976 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1