Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4b6a2c129c9f7b2…

MALICIOUS

PDF

81.4 KB Created: 2021-07-07 07:10:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 1456efc86e36adbd683e5eabe54493fc SHA-1: 1add3998c419a87cb74f4de0836120f59f433235 SHA-256: b4b6a2c129c9f7b21ed308c4428dfc148af9cdbfe7df46b4eb712e1dac03dcfd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Several heuristics point to the PDF acting as a link farm, directing users to compromised WordPress upload storage and other disposable hosting sites. The embedded URLs suggest an attempt to redirect users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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
  • 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://coronado1977.com/clients/54390/File/deparibibiveneropiwufad.pdf In PDF document text
    • http://www.cafeinca.com/img/public/contenido/file/66067568853.pdfIn PDF document text
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/ee761940604353eceb5bf6174da016ae/pewivugosegafu.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/l3hamfboal3gkbnt8uhs4l8spr/29396306547.pdfIn PDF document text
    • https://zanhotel.ro/beficientconsultingFiles/file/daliwesojinekuw.pdfIn PDF document text
    • https://wrd13.com/force/file/mebarusifodiweladubofolu.pdfIn PDF document text
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/qm33aa0rb3u2u72pbdcdt15l70/56805967735.pdfIn PDF document text
    • https://musikkursus.dk/userfiles/file/3171215730.pdfIn PDF document text
    • https://foxtailmag.net/wp-content/plugins/super-forms/uploads/php/files/ba8a8d496a496399d1a7fdb8ac723253/felotowuwajiriv.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086942ad8fb1---fezejaxowomarizenilowovud.pdfIn PDF document text
    • https://facade-metal.ch/ckfinder/userfiles/files/zigositeda.pdfIn PDF document text
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160df10ec5aae1---73490879902.pdfIn PDF document text
    • https://archltginc.com/wp-content/plugins/super-forms/uploads/php/files/8711e869f8122e10680d6d8aa55a186a/gigexiko.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b9ddf57491---vitonafobalirabop.pdfIn PDF document text
    • http://quickvideo.nl/userfiles/file/21149143744.pdfIn PDF document text
    • http://thepnguyentran.com/media/ftp/file/59654546486.pdfIn PDF document text
    • http://fixafilm.se/userfiles/file/79707921013.pdfIn PDF document text
    • https://petkasem2hospital.com/images/upload/userfiles/files/kapor.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/d7aa1e4c07dcb3642eab2635f1b97931/kewevuzeturimomiza.pdfIn PDF document text
    • https://canadiancontractorservices.com/wp-content/plugins/super-forms/uploads/php/files/3f02usu1nvbvs8hu6e96rfisl2/8498889987.pdfIn PDF document text
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/0d01748c624f394747262a70d3690ce9/kapolerever.pdfIn PDF document text
    • http://ahchala.com/img/file/99215946613.pdfIn PDF document text
    • https://pcstaiwan.com/ckfinder/userfiles/files/vekixedutapuz.pdfIn PDF document text
    • http://geostudio.eu/userfiles/files/tejofotugafexunonajo.pdfIn PDF document text
    • http://dermalab.pl/userfiles/file/nevixuwisoposavo.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a7084e8af18---53974673265.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=right+triangle+trigonometry+finding+missing+sides+and+angles+answersPDF 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_off0000d74e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD74E 17692 bytes
SHA-256: 2b9098de388028065cc9ea2e83fbed2d0ec9058d74ee068e72514544042632b0
font_01_sfnt_off000105d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011deb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DEB 11044 bytes
SHA-256: 9c3d5cd2fe7d7b0609ae4d50404f1acac0e2d3ce4c458f6e4f22a02110b7b892