Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc1cdca08ddf6b57…

MALICIOUS

PDF

80.4 KB Created: 2021-09-18 18:50:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7f1c373bfe70ddcc6900a5d7a2b2a891 SHA-1: 8b402c788f22d43e70fb0356e1f670ea0ed31b9e SHA-256: dc1cdca08ddf6b5781fdea26aa8e7c2a0e3e32066d28fd5c2131cfeca42147fb
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. It contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, suggesting it functions as a link farm. The embedded JavaScript likely facilitates the redirection to malicious sites, potentially for phishing or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://nomylo.ru/uplcv?utm_term=types+of+play+store
    • http://taigesw.com/upload/files/jodevuxixojorubawo.pdf
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/92204021387.pdf
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/16140636d93331---2898492405.pdf
    • http://phdpecs.hu/userfiles/files/68268796390.pdf
    • http://www.reeder.ee/files/filemanager/jegapazapezatuwobuk.pdf
    • http://madveras.com/ckfinder/userfiles/files/54057632264.pdf
    • http://sowiik.pl/userfiles/file/xuxebabizibapawaxirumidi.pdf
    • http://glina-master.ru/admin/ckfinder/userfiles/files/boboreziwosimofazegaxeze.pdf
    • http://haphadoor.com/upload/files/petitutavexidusokikoru.pdf
    • http://ikuma-car.com/js/upload/files/jizanu.pdf
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1614049c771e0c---19378930707.pdf
    • https://zaragozadenoche.es/upload/files/vajebo.pdf
    • https://osiindia.org/ckfinder/userfiles/files/13479050707.pdf
    • http://uslugi-ogrodnicze.pl/pliki/File/xebisu.pdf
    • http://zhuxintrading.com/uploads/ckfinder/files/20210916/16317988647242.pdf
    • http://agronlogistics.com/userfiles/files/zujawin.pdf
    • https://officialbacknumber.com/editor_up/ziduxovomejosizok.pdf
    • http://sns.hu/_user/file/navidupokatuzipiwu.pdf
    • https://ville-saintleonard.fr/pdf/48787378156.pdf
    • http://architettomontanino.eu/userfiles/files/fekawawigeguguba.pdf
    • http://hwayinn.com/image/files/20210911_115036.pdf
    • http://bezagsecurity.cz/userfiles/wopiwefowogenopubemo.pdf
    • http://sjar-tech.com/uploadfile/file///2021091118082341.pdf
    • https://coverline.ro/userfiles/file/xidilokuduwasilekoriles.pdf
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f99b32db2d---18174625360.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_off0000d882.bin
8e3fdca595c04ff9f77cc993f5f810eea0417016127fada2c7a0ab540a8780c2
pdf-font-stream PDF embedded font (sfnt) at offset 0xD882 10232 bytes
font_01_sfnt_off0000efb4.bin
1a15d066e650aba103c9ce5a302fdfd9cff2f9a50b28ad750237ba6dc2c4382e
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFB4 16976 bytes
font_02_sfnt_off00011bd5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11BD5 16792 bytes