Malicious PDF — malware analysis report

Static analysis result for SHA-256 bfe68c384c66df1b…

MALICIOUS

PDF

75.2 KB Created: 2021-10-23 02:02:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 5161f2eef2733129afd20d2cc7ba8830 SHA-1: f91e5314360e0747a479795669cd4a85c774cd88 SHA-256: bfe68c384c66df1bb888d30b26572a85ce3572ef82e376a59c3623864c8d1b73
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as a phishing trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous links, many hosted on disposable domains or compromised CMS uploads, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://bankubezpieczen.pl/userfiles/file/sajidapizekaguluna.pdf In PDF document text
    • http://sz-frp.com/pic/20211008194505909.pdfIn PDF document text
    • http://greensquares.in/userfiles/file///fadexiwuw.pdfIn PDF document text
    • https://angkaganjil.com/contents/files/dexipa.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/abd33ff9c9038c2573adc8f200f85fdb/7093212990.pdfIn PDF document text
    • http://teusz.pl/UserFiles/file/13610867115.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614af717e329d---puzarafilubuzapes.pdfIn PDF document text
    • http://scoutpate.com/userfiles/file/211798374.pdfIn PDF document text
    • http://iglozawiercie.pl/zdjecia/file/kuxiribowakofix.pdfIn PDF document text
    • http://obkladacstvikolar.com/content/85535099892.pdfIn PDF document text
    • https://webmanagement.jbclub.ro/images/file/23549901565.pdfIn PDF document text
    • https://weekendtripskolkata.com/userfiles/file/mewopanasoritabikixowoxa.pdfIn PDF document text
    • https://rdsdealers.com/ckfinder/userfiles/files/93071696242.pdfIn PDF document text
    • https://portugaliaimagyarok.com/ckfinder/userfiles/files/17961706788.pdfIn PDF document text
    • https://hiddencliff.kr/FileData/ckfinder/files/20210914_663105149243AEFF.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/k2i7t765j35ac5svu21audnftd/58643652744.pdfIn PDF document text
    • https://www.tzounakos-insurance.gr/ckfinder/userfiles/files/samexe.pdfIn PDF document text
    • http://sisparts.pl/zdjecia/fck/file/dawefupozo.pdfIn PDF document text
    • http://jagatjyotischool.org/jagatjyotischool/userfiles/file/627353093.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/25e19d09295a770cee266dd87b447c30/wutagawukurukavo.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615c7492531db---47698252380.pdfIn PDF document text
    • https://greenways.at/userfiles/file/kijupixasalinasuxaroruno.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/1hHberoKktI/uplcv?utm_term=sweetcorn+fritters+babyPDF 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_off0000c1b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1B0 17516 bytes
SHA-256: 82d9273f107b6aef1b0fe1ae57daf187797178e966984f5efb02bbfb68c3b8b9
font_01_sfnt_off0000eecd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEECD 10700 bytes
SHA-256: 12110307af001d6e8ac7114cd15e7ba29dcc707df43fbed69b4bae2483fc80ba
font_02_sfnt_off00010793.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10793 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1