Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5bd6b782da5d5ea…

MALICIOUS

PDF

87.7 KB Created: 2021-09-23 17:32:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 5a567641ef758604cb68139eaada0f66 SHA-1: 605429826adaa45b321ab1188f5eeabe8ec9b89b SHA-256: f5bd6b782da5d5eaf5d8ad183c99f7ca171715cee305621fb728f90782033f8d
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and multiple external URIs, with one heuristic identifying it as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution by directing users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 6

  • 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.
  • 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 http://huijingweb.com/upload_fck/file/2021-9-2/20210902120041386620.pdf In PDF document text
    • http://aftp.bg/userfiles/file/bajekigabesamewot.pdfIn PDF document text
    • http://mackielaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/62207431147.pdfIn PDF document text
    • https://bloomlight.pl/_bloom/file/vafakutag.pdfIn PDF document text
    • https://bimstudioinc.com/media/files/zogiregunavojep.pdfIn PDF document text
    • http://inkjetartandimage.com/Uploads/file/letamitazop.pdfIn PDF document text
    • http://samtekelektrik.com/files/jalimupezuvopepopada.pdfIn PDF document text
    • https://cursosadistanciayonline.com/medios/files/roverokejimeg.pdfIn PDF document text
    • http://lnhaihui.com/userfiles/file/20210913142340_1739037110.pdfIn PDF document text
    • http://photo-poligrafic.ru/ckfinder/userfiles/files/xizutesofojo.pdfIn PDF document text
    • https://www.agro-zavod.ru/app/webroot/js/ckfinder/userfiles/files/domotibaki.pdfIn PDF document text
    • http://manu-transport.com/documents/file/pikeganizipilupifalola.pdfIn PDF document text
    • https://adikkeempat.com/contents/files/tawanusejab.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614914f48d15f---96842764217.pdfIn PDF document text
    • https://sheenabusesandcoaches.com/userfiles/file/70057445604.pdfIn PDF document text
    • http://xn--h1aaebajlcgx.xn--p1ai/sadm_files/nopenek.pdfIn PDF document text
    • http://topstec.com/d/files/21473451680.pdfIn PDF document text
    • https://funstore.dialog.org/userfiles/file/7479310395.pdfIn PDF document text
    • http://vitalchurchesinstitute.com/files/file/63749721750.pdfIn PDF document text
    • http://grandwatergatehotel.com/upfile_hotel/files/vejirufapeme.pdfIn PDF document text
    • http://barexkft.hu/userfiles/file/8834501708.pdfIn PDF document text
    • https://www.karelo.com/uploads/File/gisam.pdfIn PDF document text
    • https://subded.org/userfiles/file/71243850549.pdfIn PDF document text
    • http://archiw.gbpopatowiec.pl/img/upload/files/20780582320.pdfIn PDF document text
    • https://autoradiator.mn/uploads/ckfinder/files/57208668377.pdfIn PDF document text
    • https://jeneifogaszat.hu/cikkdata/files/70561142117.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=j210f+flash+file+4filePDF 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_off0000f1b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1B5 18588 bytes
SHA-256: e728c8e635e1a2ca7ccb63cbfe202fc656a615127a101d07347bfd11e12070e1
font_01_sfnt_off00012186.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12186 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001399d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1399D 10252 bytes
SHA-256: e092e2fafe2ccdaea1fda821b9e81b2ac3b49aead044e808534c0d55f06c5ac7