Malicious PDF — malware analysis report

Static analysis result for SHA-256 819473a6dc2988f5…

MALICIOUS

PDF

82.2 KB Created: 2021-09-19 09:53:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 4f951914c65752ca48c057c5771d3b2b SHA-1: a0c8cff41fb34a064317db6f615f6a214b454192 SHA-256: 819473a6dc2988f55cb88b90a7ad8655b38d930df2eea3f3c2429260cc386060
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also contains numerous external URIs, many of which point to disposable domains and are structured as a link farm, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or trojan delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

Heuristics 6

  • 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.
  • 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://catamma.ru/uplcv?utm_term=countthings+app+free PDF link annotation
    • https://red-adlay.com/upload/files/294805083.pdfIn PDF document text
    • http://beganijewellers.com/ckeditor/ckfinder/userfiles/files/40402737046.pdfIn PDF document text
    • http://synergytaekwondo.com/click2buy_newp/userfiles/file/bojiwizavijeb.pdfIn PDF document text
    • http://ourpreferred.com/userfiles/files/pakafu.pdfIn PDF document text
    • http://abwsalisbury.com/uploads/files/58484810827.pdfIn PDF document text
    • http://mazraeir.com/images/upload/files/zemeduruwafumakexixega.pdfIn PDF document text
    • http://elite-nails.pl/Upload/file/84472630768.pdfIn PDF document text
    • http://smelawservice.com/file_media/file_image/file/54504233420.pdfIn PDF document text
    • http://henskeschildersbedrijf.nl/upload/2450980592.pdfIn PDF document text
    • http://www.smwiarus.pl/ckfinder/userfiles/files/42840726669.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1614350d59512a---73223695331.pdfIn PDF document text
    • https://12shio1.com/contents/files/7408824255.pdfIn PDF document text
    • https://eltechma.com/zdjecia/fck/file/26367343826.pdfIn PDF document text
    • http://website-design-company.in/dev3/damodar/ckfinder/core/connector/php/userfiles/files/mujupunolofugisi.pdfIn PDF document text
    • https://rotitelor.com/contents/files/penujudupafitus.pdfIn PDF document text
    • https://westhigienia.hu/editor_up/fadupurebuwutiwadigu.pdfIn PDF document text
    • https://tdfstore.it/file/fubabeteruzalisixal.pdfIn PDF document text
    • http://hillsdalehorseboarding.com/ckfinder/userfiles/files/vusuwimiligiwerudidivi.pdfIn PDF document text
    • http://bunny888.com/ckfinder/userfiles/files/logadejifudesoselinojeref.pdfIn PDF document text
    • http://svenskafik.se/uploads/fckeditor/file/56722631895.pdfIn PDF document text
    • http://xn--h1aeekk.xn--p1ai/files/file/nufugevonew.pdfIn PDF document text
    • https://rajaketiga.com/contents/files/42882551455.pdfIn PDF document text
    • https://energiadirect.pl/application/resources/ckfinder/userfiles/files/54039525476.pdfIn PDF document text
    • http://platypusspot.org/uploads/ckfinder/userfiles/files/5469280701.pdfIn PDF document text
    • http://plusk-car.com/js/upload/files/badavirofet.pdfIn PDF document text
    • https://wsbtitan.com/images/file/vojife.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16135e000d63c2---lufaxufezebelamemolizep.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_off0000da80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA80 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f292.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF292 18576 bytes
SHA-256: 96b8eb2111a0edafd24f29eff6a0140fd910ab345d80242d27d79a0fac982f13
font_02_sfnt_off000122ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122EC 10724 bytes
SHA-256: ccb3627b08547b2ca5172e834d2c9d812bdde55ce9f24de237413f2eafd16533