Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc4949f050b91c75…

MALICIOUS

PDF

84.5 KB Created: 2021-09-16 14:58:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 129597b02da32e6ffdc202f4d9b821f4 SHA-1: d632d7b9cbd9c7ad00d9c8db3cb42c64ced15b98 SHA-256: bc4949f050b91c75612e2bf99c8d3bb6b4ff8f8faf3981ae68d82c845477436f
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 ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous embedded URLs pointing to potentially compromised or disposable hosting. The presence of external URIs and link farms suggests an attempt to redirect users to malicious sites, likely for phishing or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 http://kemmurad.com/webroot/img/files/46179536564.pdf In PDF document text
    • http://somsit.com/ckfinder/userfiles/files/67646136477.pdfIn PDF document text
    • http://trungtamsangloc.vn/uploads/ck_upload/files/juregof.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1613d642e9b4ac---fitujanoxaliporaxivobu.pdfIn PDF document text
    • http://srihemkuntschoolint.com/slbdavbatala/userfiles/file/rezegisoligotuninenixu.pdfIn PDF document text
    • http://vekosgroup.ru/userfiles/file/22340458856.pdfIn PDF document text
    • http://longruiglass.com/ckfinder/userfiles/files/20210913_073756.pdfIn PDF document text
    • https://gdaniec.com/upload/files/bonurotezegoguk.pdfIn PDF document text
    • https://bushregenerators.info/userfiles/files/89373365132.pdfIn PDF document text
    • https://iuoshili.com/upload/users/files/57511761609.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b416ab4810---ruturawefemasowaw.pdfIn PDF document text
    • http://thegioituigiay.net/uploads/files/pirajanozasegujakekejuka.pdfIn PDF document text
    • https://sailstudy.in/ckfinder/userfiles/files/mejizumunepavijebu.pdfIn PDF document text
    • https://fairtradeportal.pl/userfiles/file/55260948611.pdfIn PDF document text
    • https://fond.ru/userfiles/file/dubamowubefegugo.pdfIn PDF document text
    • http://3qlohas.com/CKEdit/upload/files/dozogafenabilaku.pdfIn PDF document text
    • https://netiko.fr/img/Data/file/pixaxerof.pdfIn PDF document text
    • http://lawyermo.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/16569402912.pdfIn PDF document text
    • https://anitacalderon.com/ckfinder/userfiles/files/14399794741.pdfIn PDF document text
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/161402b1285c04---22877634411.pdfIn PDF document text
    • http://gloteckr.com/upload/editor/file/67997794615.pdfIn PDF document text
    • https://anna-bel.com/app/webroot/files/userfiles/files/12490135052.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=how+to+flash+your+android+phonePDF link annotation
    • 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_off0000e52f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE52F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD41 17620 bytes
SHA-256: 414b488aa19e682ee402cfb704a573bee5e74a7c52f27b4d896f526267a7a800
font_02_sfnt_off00012b5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B5C 10884 bytes
SHA-256: a686490218ac544e7cb55bea0c9d69075d312960c387525ca1b174fbb03f0e27