Malicious PDF — malware analysis report

Static analysis result for SHA-256 53250fb31c94e799…

MALICIOUS

PDF

76.9 KB Created: 2021-09-18 06:08:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e64cf8bdbbb41fa49357200b477d50bf SHA-1: f3ed993ee7265f16a67fff4a831ebde3bd247776 SHA-256: 53250fb31c94e7995c947440de8a1b2ddda95502102407591f83ec6a8b9aef45
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous external URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The primary function seems to be redirecting users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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
  • 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.
  • 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=ff3+map+snes PDF link annotation
    • https://cukimentescukraszda.hu/files/files/80643093983.pdfIn PDF document text
    • http://corkpotters.com/images/lirivadod.pdfIn PDF document text
    • http://vcelari.naceradec.cz/includes/ckfinder/userfiles/files/wimajodudonadoker.pdfIn PDF document text
    • https://navliecky.net/userfiles/file/dimorarinovozefo.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1612fecc39b588---37131719753.pdfIn PDF document text
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/161341ed3cdaf4---lipikiki.pdfIn PDF document text
    • https://ikansambel.com/contents/files/30665532129.pdfIn PDF document text
    • https://songod.vn/uploads/image/files/pisuvegezebek.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ba5c3c8d51---50432930155.pdfIn PDF document text
    • https://ww150004.linebot.net/upfile/files/20210909194954.pdfIn PDF document text
    • http://hiniceshine.com/upload/fuzovajatar.pdfIn PDF document text
    • http://roberlo.cz/www/files/file/49480294699.pdfIn PDF document text
    • http://businessdevelopmentcenter.pl/uploads/userfiles/files/73375834789.pdfIn PDF document text
    • http://nasfthr.com/userfiles/file/kowekuvoma.pdfIn PDF document text
    • https://clicksnepal.grnca.org/img/files/files/midikejexenategudirezovot.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144dc7967d8c---37156072080.pdfIn PDF document text
    • http://ranjitabiswas.com/userfiles/files/safitolusagav.pdfIn PDF document text
    • http://delannahotel.com/user_img/file/pofixuxenokiken.pdfIn PDF document text
    • http://kondicionery-fryazino.ru/upload_picture/file/6901765075.pdfIn PDF document text
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/1hq447s4mtckq33a5a5j91pv82/81288134372.pdfIn PDF document text
    • http://giovanniseneca.eu/userfiles/files/20610799344.pdfIn PDF document text
    • http://cuacuongiare.vn/upload/files/44867366782.pdfIn PDF document text
    • http://zhhyhb.com/uploadfiles/files/pezatulogomuwik.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_off0000cc59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC59 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e470.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE470 10212 bytes
SHA-256: b883ece9f5c3dadf68e0bc5ddc2425cc7ad5dcf14c87bb3612cd27c249d760d2
font_02_sfnt_off0000fb4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB4F 16468 bytes
SHA-256: 8336a1d75bc79a3b8012352554c821ab7cef203f3c6400fc936244a0f89739e6