Malicious PDF — malware analysis report

Static analysis result for SHA-256 b38f98fde0f5e1eb…

MALICIOUS

PDF

81.1 KB Created: 2021-09-16 19:46:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 3e56f45f465987ba281da27a1aca81f9 SHA-1: da0f9ef52b19d25dd1bbdc2ee9104a00b52a9a53 SHA-256: b38f98fde0f5e1eb6bd779ca7ddcbd63a0afeae148f60602e9223cb037264885
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous external URIs, including one with a 'cracked android phone' UTM term, suggests a phishing or malware distribution lure. The file's structure and embedded links point towards it being part of a link farm designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://synerhu.ru/uplcv?utm_term=cracked+android+phone PDF link annotation
    • https://korankertas.com/contents/files/piroroxifiwerelaxubegofax.pdfIn PDF document text
    • http://alles-vom-schreiner.de/userfiles/file/dumemitowuzokok.pdfIn PDF document text
    • http://rcp-ranstadt.us/files/60461544815.pdfIn PDF document text
    • http://cadelupo.it/userfiles/files/nojokuzejaferovol.pdfIn PDF document text
    • https://badeluxe.com/userfiles/files/kotuvavelixi.pdfIn PDF document text
    • http://linza-market.ru/upload/files/pobosan.pdfIn PDF document text
    • http://cofetariafraguta.ro/UserFiles/file/rasofimobeduziwu.pdfIn PDF document text
    • https://millersexpress.com/userfiles/file/jebowigorugoxidedizaj.pdfIn PDF document text
    • https://huaku3c.tw/uploads/files/202109150653484661.pdfIn PDF document text
    • http://falconfam.com/ckfinder/userfiles/files/medeje.pdfIn PDF document text
    • http://kmsenior.org/file/files/gawajobigavewurutexep.pdfIn PDF document text
    • http://xn--sanitrprofi-p8a.ch/fckeditor/editor/images/file/tokufogilobisixuwuworejok.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161393cffda2f4---vifodupedewabekabazut.pdfIn PDF document text
    • https://dcimx.com/files/61101585502.pdfIn PDF document text
    • http://windmill-bv.com/userfiles/files/mujisijagoxupogomumunu.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/tewirusedovo.pdfIn PDF document text
    • http://hoaphathotel.com/luutru/files/88070397150.pdfIn PDF document text
    • http://kool-house.com/upload/editor/file/58706124368.pdfIn PDF document text
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/161314593be43a---71024969262.pdfIn PDF document text
    • http://daedukgs.com/admin/fckeditor/data/file/20210909120606.pdfIn PDF document text
    • http://myjobcareer.net/userfiles/file/2021091523584673499.pdfIn PDF document text
    • http://hindustanadvancedsolution.com/t/tutorfirm/uploads/ck/files/14107521165.pdfIn PDF document text
    • http://zrdb-drogbud.pl/Upload/file/90246095575.pdfIn PDF document text
    • http://casaatlantida.com/userfiles/file///43910121301.pdfIn PDF document text
    • http://radis-rrl.ru/userfiles/image/66971551530.pdfIn PDF document text
    • http://uspeh-kursk.ru/ckfinder/userfiles/files/wirapekorexawe.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_off0000d864.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD864 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f076.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF076 18196 bytes
SHA-256: 5196ac72a5a8569d309ff9f442abe9873e6d227683252d483a568ac0b2acf2ff
font_02_sfnt_off00011f18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F18 10424 bytes
SHA-256: 8b6311350ffce9bea31859548ed46cda51412491a9ca393e68bed891f0ca0c7e