Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1a2839627d0ab31…

MALICIOUS

PDF

68.7 KB Created: 2021-09-26 07:10:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 13dbd2c03f5a15eff6e2864ec1ef8606 SHA-1: 61022a6665d562ddf067f37e0c4825008d69fce9 SHA-256: f1a2839627d0ab317c7e6f6375ff2cfd22ae2c73a1fadc3331e0517895a31a87
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious content. The presence of numerous external URIs, many hosted on disposable domains, suggests a link farm designed to redirect users to potentially malicious sites. The document body is heavily obfuscated, but the overall structure and URL patterns point towards a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://allytemp.ru/uplcv?utm_term=good+free+ringtone+apps+for+android PDF link annotation
    • https://www.mnogotrop.com/ckfinder/userfiles/files/renupadubusenemudateba.pdfIn PDF document text
    • https://borsalino.ro/imagini_ws/judatukorixawarupimarik.pdfIn PDF document text
    • http://kamkmori.cz/ckfinder/userfiles/files/2428068388.pdfIn PDF document text
    • https://mimzyonline.com/userfiles/file/10470199426.pdfIn PDF document text
    • http://ilsogno-bomboniere.com/userfiles/files/49342794896.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c42cd2469f---nagebebefox.pdfIn PDF document text
    • http://eichler-kammerer.de/funis.pdfIn PDF document text
    • https://alshaabcoop.com/userfiles/file/gubijalolonorisipopuxo.pdfIn PDF document text
    • http://myphamnanyno.com/luutru/files/milufoxotevimateviwiko.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/1614f33b6cae40---45292035181.pdfIn PDF document text
    • https://thefertilizergranulator.com/d/files/47714142740.pdfIn PDF document text
    • http://fine-cottage.ru/userfiles/file/romuwunezot.pdfIn PDF document text
    • http://rurisnet.org/images/file/guwajopopetipenuwijeza.pdfIn PDF document text
    • http://aan.kz/ckfinder/userfiles/files/xuwuderulexikotapitef.pdfIn PDF document text
    • https://trade.inter-ural.ru/ckfinder/userfiles/files/tuwiwigezepiwerarupesenuk.pdfIn PDF document text
    • https://girilawfirm.com/content_files/files/59159571870.pdfIn PDF document text
    • https://deltarealestate-eg.com/userfiles/file/xuzawovaxaxo.pdfIn PDF document text
    • http://www.zywawiara.pl/pliki/67041966713.pdfIn PDF document text
    • http://torgoborud.org/images/file/73860422361.pdfIn PDF document text
    • https://aletihad-group.com/userfiles/files/tugilobipofavorivegutibe.pdfIn PDF document text
    • https://eccdc.org/application/webroot/userfiles/file/38701597470.pdfIn PDF document text
    • http://ksiclubcom.ksiclub.org/svnprojects/DHD/Source/images/files/fetigedolapamitenuleju.pdfIn PDF document text
    • https://webmanagement.jbclub.ro/images/file/15732274538.pdfIn PDF document text
    • http://desushibar.com/userfiles/file/sewipupenotafixasazosijon.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_off0000adc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xADC5 14980 bytes
SHA-256: bc7bb7bfc6c988db30af88e80bdeb8357114633fda156bc47e5822ab9c722143
font_01_sfnt_off0000d2f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2F2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eb09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB09 10664 bytes
SHA-256: c0d3ed5c748193f87d0e36decf33fe1ad440046da606d8f6fa0deaf2bf3c9ce3