Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1ac8db233f83202…

MALICIOUS

PDF

73.7 KB Created: 2021-06-29 21:02:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 43674bdb3ff835902322713cf824b998 SHA-1: c41f28c46c968d681bbf61969ab92347c73ac38c SHA-256: c1ac8db233f832025e1e6222c4ca8439e9537b0f633d709539d83a4c8e97b461
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The document body is heavily obfuscated and unreadable, providing no direct content clues, but the heuristics and URL analysis are sufficient to infer the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://my-natural-style.net/upload/files/walamudedalomuvoporon.pdf In PDF document text
    • https://davebakeragency.com/wp-content/plugins/super-forms/uploads/php/files/748061c51337d9aa424bcc1bf7049f17/febefaranabiveruzoxa.pdfIn PDF document text
    • http://tablica-nieruchomosci.pl/uploades/fckeditorfile/24531942488.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c2678eb8de1---xujojo.pdfIn PDF document text
    • https://hoangnhataudio.vn/media/files/15359514394.pdfIn PDF document text
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/1341e90f40d8eb1ca077029e8983b383/30314819983.pdfIn PDF document text
    • http://iseveranscopy.com/upload/editor/file/pivokefaxipamagejixe.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a889426be7f---sipomejowebi.pdfIn PDF document text
    • http://outspokenholland.com/userfiles/fckFile/20210516104612.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160850cc33c580---50760051513.pdfIn PDF document text
    • http://studioarchperissinotto.eu/userfiles/files/36039659268.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/88a34412a34f0c2c644798f2d0623caf/60665250676.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160708bd8b407e---88877042198.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/2f53fcde2c74eb629095ae109d429311/nadukunug.pdfIn PDF document text
    • https://juhaszautovill.hu/userfiles/file/dimomexe.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/2aqna9r9eoj4d4krbl55c2fhkt/96726922126.pdfIn PDF document text
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/cc7509b6d517a398b0991490f63077c8/wudenojorenosupol.pdfIn PDF document text
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607ff07d98c9e---repojaganujized.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/u6i7mkln73v0tjji64tut96mro/podijuverudewofov.pdfIn PDF document text
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160adfad9e8094---luzafozo.pdfIn PDF document text
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/fd4d90cf8f02d47298ce24e3fecf39d0/lowigawi.pdfIn PDF document text
    • https://larioenergy.net/uploads/file/fiduzubelikurozenula.pdfIn PDF document text
    • http://albatrossmrn.com/konadnew/userfiles/file/15003255394.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=ode+music+standardsPDF link annotation
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/2abc38f7cf12b2d1c9ad3e1a215c26bd/25350211691.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_off0000c217.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC217 10492 bytes
SHA-256: af80304405d1630582bead744097845d867798d16a79e4e4446bcf00d3eb6f02
font_01_sfnt_off0000d9f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f20b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF20B 15544 bytes
SHA-256: 545c7ec5d2e4515ce4e39bacba249d10242508e977d12f8d72eb6a548e4c475a