Malicious PDF — malware analysis report

Static analysis result for SHA-256 187376fdab2fb603…

MALICIOUS

PDF

88.1 KB Created: 2021-09-22 20:54:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7c38e9424f2a0dc854458435dc09d619 SHA-1: 65bc4decaa1ec745155a5c89ca93a770fe53cdf3 SHA-256: 187376fdab2fb6034c22e6183f5fddd9ef27e87a36c3adaaf11ff506a85bd7cb
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. The file's structure and numerous external links are consistent with a malicious document designed to lure users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/376bcfe83ba0fe8b79163720e01b3970/xelenut.pdf In PDF document text
    • http://lukasikgroup.pl/Image/files/vedexusinepivuxosefezak.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/6206fe540c57d6d30cbb300cbf559380/42523507664.pdfIn PDF document text
    • https://premiersuli.hu/files/files/telifunuxeled.pdfIn PDF document text
    • http://sbs-group.co/userfiles/files/9477078028.pdfIn PDF document text
    • http://eraldocomo.it/userfiles/files/nuburefevibone.pdfIn PDF document text
    • http://www.dgtrans.co.th/login/ckfinder/userfiles/files/17711013757.pdfIn PDF document text
    • https://berbagiangka.com/contents/files/13805311383.pdfIn PDF document text
    • https://siphouse96.com/wp-content/plugins/super-forms/uploads/php/files/bc37159371eecb0fbb504a601e850070/40817534886.pdfIn PDF document text
    • https://martas.vodrsport.cz/uploads/files/pegabijawixabuluvorudoxi.pdfIn PDF document text
    • http://dxczx.com/ckfinder/userfiles/files/20210919_211547.pdfIn PDF document text
    • http://bonaparte-kerkrade.nl/fckeditor/ckfinder/userfiles/file/7499322988.pdfIn PDF document text
    • http://harekatmemuru.com/images/Media/files/36730392039.pdfIn PDF document text
    • http://net-work.cz/data/file/27554704540.pdfIn PDF document text
    • http://www.77ice.com/upload/files/reloxif.pdfIn PDF document text
    • http://coeb.eu/userfiles/files/vujisexikodukovapige.pdfIn PDF document text
    • http://cyklo-sport-servis.cz/UserFiles/File/futunosusekugesofadub.pdfIn PDF document text
    • http://www.ecvbrass.ch/user/web/file/deguronivomezaxolofotejad.pdfIn PDF document text
    • https://cribpointonline.org/cribpointonline/userimages/file/jenidukakesire.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/161312f477e960---66673047572.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b33bb92acc---65948880455.pdfIn PDF document text
    • http://motocams.cz/ckfinder/userfiles/files/81032372676.pdfIn PDF document text
    • http://hidropro.hu/upload/linexud.pdfIn PDF document text
    • https://xn--p3t29jo1ed4o4xw.tw/upload/files/68111502584.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/i4ik93k1eila1pbj3odbtbboak/72692503257.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/38033257072.pdfIn PDF document text
    • http://hiroshima-teishaku.com/userfiles/file/4941915604.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=adb+backup+contactsPDF 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_off0000f384.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF384 10452 bytes
SHA-256: 4a6c4fced1c2c4e235db8d3626a786b8369d1f14ab8174c89da562399faf3204
font_01_sfnt_off00010b32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B32 18268 bytes
SHA-256: 37ad40b611f27256985f09fd288b77bac78c3bf26ebaea4ea9f3b3c2965083ac
font_02_sfnt_off00013aa8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13AA8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1