Malicious PDF — malware analysis report

Static analysis result for SHA-256 3131a0a11addcde4…

MALICIOUS

PDF

73.0 KB Created: 2021-09-17 12:14:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7dc90db3e53337f2494ae98384214d99 SHA-1: e6848b5121085032c74b67c9438417ba70ac2bed SHA-256: 3131a0a11addcde4a580a34f457d0cf534381fad30fcfe41eec54feb7a8798b6
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://synerhu.ru/uplcv?utm_term=ola+tv+11+apk
    • http://driver-jazda.pl/upload/file/jasozipewozimuva.pdf
    • https://www.hemingway.bg/app/templates/js/ckfinder/userfiles/files/kowudewa.pdf
    • http://velocimapper.com/webfiles/file/togidexeverigom.pdf
    • https://giga-tronics.com/userfiles/files/dabumuzerifuwanoxowo.pdf
    • https://renteci.com/imagens/file/77731026829.pdf
    • https://privatecambodiatour.com/userfiles/file/belesimajavur.pdf
    • https://yptea.com/data/fckeditor/files/fobunikanugif.pdf
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/dhkpfcj866e83pgc9apo46c0do/54788723540.pdf
    • https://lenaoyunlar.net/calisma2/files/uploads/jemafep.pdf
    • http://eprobatdz.com/ckfinder/userfiles/files/gazerip.pdf
    • https://ismet.com.br/ckfinder/userfiles/files/vesowopamirubewud.pdf
    • https://edusfera.pl/upload/file/xakizanapaxibasi.pdf
    • http://bennett-legal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/42955904069.pdf
    • http://childconnect.com/swi/fckfiles/file/radar.pdf
    • https://nutrishop.in/ci/userfiles/files/6725501384.pdf
    • http://modnyi-buket.ru/uploads/files/15204767977.pdf
    • http://familiegravesen.dk/userfiles/file/derovategutajasoxuruw.pdf
    • http://vitalenzyme.com/uploads/fckupload/file/26589836691.pdf
    • http://spodne-pradlo-2bpoint.sk/UserFiles/File/bimunaboxogegurapavawek.pdf
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/mqgp4e8hhs7030e8iu4sorqso3/winesaxadetipuwu.pdf
    • http://topflexsports.com/uploads/fugizezukare.pdf
    • http://gzperson.com/uploadfile/files/rinatotomopuvatuboj.pdf
    • https://conexusinternational.com/ckfinder/userfiles/file/54989443768.pdf
    • http://oumkua.com/userfiles/file/76380527982.pdf
    • http://hoangminhsaigon.vn/@dmin/js/ckfinder/userfiles/files/46825313154.pdf
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/67ki7jfahmpr4e8nk5ei0ijdie/xizobufere.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bfde.bin
8a73c4f444c1c5f14a0cf7e09820fe08d56d065d34414220424b5e3f383fa38b
pdf-font-stream PDF embedded font (sfnt) at offset 0xBFDE 16164 bytes
font_01_sfnt_off0000e8f4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE8F4 16792 bytes
font_02_sfnt_off0001010a.bin
6745e3c7b3357c1bb1cca2996b9783ed32d3fec3080da0b743e111f4e814bf3a
pdf-font-stream PDF embedded font (sfnt) at offset 0x1010A 9764 bytes