Malicious PDF — malware analysis report

Static analysis result for SHA-256 b31a4a6d66997926…

MALICIOUS

PDF

87.8 KB Created: 2021-07-08 03:50:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 34e1d6dd2b39dbf5f6bf400dde87de0b SHA-1: 4092e077bbd7255bc2a1ea6488e869083b12c695 SHA-256: b31a4a6d66997926c034afe53878ad298769b1f9ce9862a770f93eb870a6dba8
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains a large number of embedded links, many of which point to compromised WordPress installations, suggesting an attempt to redirect users to malicious content. The PDF structure and link farm behavior are indicative of a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073c3f5c6985---rikitibonogamesuni.pdf
    • http://polishingmarblefloor.it/userfiles/files/67007658378.pdf
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b86186d1fd4---35958484661.pdf
    • http://learnersdigest.org/userfiles/file/21129083769.pdf
    • https://wecafephuket.com/wp-content/plugins/super-forms/uploads/php/files/6appgfflconpa0ifa09l6a70c6/bezodikesi.pdf
    • http://geoplan.su/userfiles/file/33059895115.pdf
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/hgro4id0258so3h3pf8uk789mj/9789247396.pdf
    • https://wills.sg/wp-content/plugins/super-forms/uploads/php/files/d224918d56f442b7d99dfac11ff4ff90/45279199507.pdf
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160976b67bfea6---rivepefijamopa.pdf
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/b4fdf84897b1ce9956a2fd5352123f5d/96760350696.pdf
    • http://accessiblevehicleservices.com/userfiles/file/sozatimonimesureb.pdf
    • https://www.masismarketing.com/wp-content/plugins/super-forms/uploads/php/files/d6322fa75affa7ba1e4632d721f94eb9/wuwobaniradelejufusi.pdf
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ead45b3352---72149784742.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/2l6avfvsn5ivr29i1njk56uba0/tufilefalinefurafapid.pdf
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/b4961851bee74396a4bf83f0d3c552ad/piwijadir.pdf
    • http://magogaralbamoble.com/galeria/files/15966686753.pdf
    • https://www.sixteengrams.com/wp-content/plugins/super-forms/uploads/php/files/90cnhrvpkcm9n7vhooinrsul34/vafigavokobuviniwifuxop.pdf
    • http://bluecars.pl/userfiles/file/nabenojidewufezabogefazu.pdf
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/16074c69694d7a---zevitadotene.pdf
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/81dfcb0be093899a075eb06b5a9121da/22634270483.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a973ef57d61---20203823372.pdf
    • http://oresteruggiero.com/userfiles/files/wulenotidekujil.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=what+does+it+mean+to+be+human+in+anthropology
    • 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_off0000f3dd.bin
63fadca7fc7c8da4103f7f0723b88b04295bb2d0c3e26846d55fd47436b15885
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3DD 16928 bytes
font_01_sfnt_off0001200d.bin
cdf9b261cc84a112acba25e3ece28a83709115bcfce406863879fb6d88215665
pdf-font-stream PDF embedded font (sfnt) at offset 0x1200D 11188 bytes
font_02_sfnt_off0001399e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1399E 16792 bytes