Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8f7cfa71448adb7…

MALICIOUS

PDF

81.4 KB Created: 2021-09-13 21:14:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 6e606219b15132652814e39582d167d1 SHA-1: 51ed91a89d3cf4c32d1b85ad0679a6989334043f SHA-256: f8f7cfa71448adb74cbecda697c1409d7e26feac147c133369fb9c616cae4ba7
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to other PDF files hosted on disposable domains. This structure is indicative of a link farm designed to distribute malicious content or phish for information. The ML classifier and ClamAV detection strongly support the malicious verdict.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://trongtrucsolution.com/uploads/files/bapowinajun.pdf In PDF document text
    • http://www.verneteco.com/ckfinder/userfiles/files/1119336304.pdfIn PDF document text
    • http://werder-ritter.de/UserFiles/File/mowokabedebetebuvazere.pdfIn PDF document text
    • https://keongracun.org/contents/files/80557538082.pdfIn PDF document text
    • https://gruppopolidori.com/upload/image/file/98039647788.pdfIn PDF document text
    • http://airsoft1.ro/files/file/bifibebobutenolet.pdfIn PDF document text
    • http://pitin-akutsu.com/js/upload/files/12769263362.pdfIn PDF document text
    • http://xn--b1adrijbbb.xn--p1ai/upload_picture/37895198364.pdfIn PDF document text
    • http://creativeindustries.ru/uploads/userfiles/file/84841838483.pdfIn PDF document text
    • https://giaiphapthietke.vn/media/file/files/jamorazodeba.pdfIn PDF document text
    • http://onyx-innovations.com/assets/ckfinder/userfiles/files/71590270557.pdfIn PDF document text
    • http://xn--9i1b14l32gg2dsybq3b.com/upload/fckeditor/file/43741409205.pdfIn PDF document text
    • http://islenapuntos.com/campannas/file/14254017887.pdfIn PDF document text
    • https://optimustelecoms.com/ckfinder/userfiles/files/pedipinolorekadigope.pdfIn PDF document text
    • https://padservhosting.com/userfiles/file/janatasamoxebapofemim.pdfIn PDF document text
    • https://dycmc.com/DATA/upload/files/202109091024102512.pdfIn PDF document text
    • https://asiquim.com/ckfinder/userfiles/files/sisiwerawitilariratupis.pdfIn PDF document text
    • http://sayarbobinaj.com/file/93676372384.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/i7ouu43mh7p9oph43acrvt9b81/83368520436.pdfIn PDF document text
    • https://brawlcall.jordanadams.com/ckfinder/userfiles/files/62249426753.pdfIn PDF document text
    • https://www.esicm-old.org/admin/lib/ckfinder/userfiles/files/duridowametavidowike.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612f6b3fbacdd---83618668000.pdfIn PDF document text
    • https://museuminiaturesbesalu.com/files/53398902148.pdfIn PDF document text
    • http://ever-pioneer.com/upload/files/8673316044.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=line+apk+latest+versionPDF 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_off0000d966.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD966 18112 bytes
SHA-256: 41ab00662468c0f149664a56e9c7145ec00a7011f455629fc9a0b28379d10b4e
font_01_sfnt_off0001081f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1081F 10360 bytes
SHA-256: 59a561bc3882fc27c554eb09f91cdc4a3da43c42d55c8261cba1af7d1206c653
font_02_sfnt_off00011fb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FB0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1