Malicious PDF — malware analysis report

Static analysis result for SHA-256 77cf57c2d41e1e64…

MALICIOUS

PDF

83.9 KB Created: 2021-09-02 15:31:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6cef049a15d7c9c3abcbe1a28cd5df2a SHA-1: 6824bd032632766149180ccfd19bec7cde5c41f4 SHA-256: 77cf57c2d41e1e64cde82431a32d4a182a94936c49cc80a28c3e7096decd303e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or are part of a link farm. The presence of embedded JavaScript and a high ML classifier score further indicate malicious intent. The primary goal appears to be redirecting users through a series of links, potentially leading to phishing or malware download sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://vettercycles.ch/userfiles/files/69933585088.pdf
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/16071b49ad7501---90095684129.pdf
    • http://www.dismaplant.com/ckfinder/userfiles/files/biwekamorewifijolavawiro.pdf
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160cb613c5d101---muwugimobesin.pdf
    • http://mingzhicc.com/userfiles/files/61251967179.pdf
    • https://www.qualityitalia.it/ckfinder/userfiles/files/jimenamaperagazaz.pdf
    • http://thoitrangvabaoho.com/Images_upload/files/najizejedizenimulexaxur.pdf
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c116f41ba6e---bosog.pdf
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611b84f0457d5---tivuvaz.pdf
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1606d88989aec2---futanevumovuruxux.pdf
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/11aefc87cab8bdf093abe75fd893d38f/fuvifiwufewamurokono.pdf
    • https://samarthanamparisara.org/apadmin/uploads/userfiles/files/ragasiwogezunifesizotol.pdf
    • http://k-ookuma.com/js/upload/files/60710559642.pdf
    • http://izumrud38.com/ckfinder/userfiles/files/lazuberosajadexe.pdf
    • http://udmvdpo.ru/images/files/pimunanupukugiru.pdf
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a223124e7c7---25221439237.pdf
    • http://konsultacjenaukowe.eu/Upload/file/46432531270.pdf
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160c7a177a9b2a---vigiwojiwoxu.pdf
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/4d98b83628c883e4ab216e96812283d0/10053255163.pdf
    • http://enjoy.sk/editor_uploads/system/files/61130939123.pdf
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/vqu7th1ha1er9ehss1phjc7149/sapekivubonifik.pdf
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160967e76e19cd---pilifofuduzowajapowaju.pdf
    • http://progettarecasa.com/userfiles/files/87105942693.pdf
    • https://ip-pharma.net/data/files/75507519292.pdf
    • https://bravo-hk.com/userfiles/file/tepekizedurawafodex.pdf
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609050848de44---wegutepalopi.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=castles+of+burgundy+card+game+rules+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e1d3.bin
cf161ced3e516ec01fc03782a27cc988edc8c008d26010481cd405ae6bfa4f17
pdf-font-stream PDF embedded font (sfnt) at offset 0xE1D3 11256 bytes
font_01_sfnt_off0000fbe4.bin
464e844d46f78c35b954ce6d9b99680cc21afb23933e5bc85db4419167a12203
pdf-font-stream PDF embedded font (sfnt) at offset 0xFBE4 17632 bytes
font_02_sfnt_off000129a2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x129A2 16792 bytes