Malicious PDF — malware analysis report

Static analysis result for SHA-256 e72a8cb9691f8b62…

MALICIOUS

PDF

87.1 KB Created: 2021-09-05 18:12:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: e04a1b73a14c864fa2e176a123c94c62 SHA-1: 876acaa97e519d58a838dfea29764c697f0cc9f6 SHA-256: e72a8cb9691f8b622bd9b91c2fb7a0a3a3216acd7f9e0c0fb9e9851d1996af88
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Multiple heuristics identified the PDF as a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting it's used to distribute further malicious content. The embedded URLs are likely part of a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/1607b5cfe85bf5---buvaduzut.pdf In PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607ab5e661499---41927350654.pdfIn PDF document text
    • http://gps-ambroisie.com/ressource/site-image/files/jekodusatumitulapizemu.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/2irq3a1bvk3uqk6np56ab5n98l/tamejerakiluze.pdfIn PDF document text
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/3be2b8ecd9b2e2d2d3ad0498d3ebb6bd/bezeb.pdfIn PDF document text
    • https://baoyi-chuck.com/ckfinder/userfiles/files/80779775917.pdfIn PDF document text
    • https://cashmeredreams.com/wp-content/plugins/super-forms/uploads/php/files/2ebcba22faa99a0a7ad81c947c84e202/57827190653.pdfIn PDF document text
    • http://northmarking.com/userfiles/files/mamej.pdfIn PDF document text
    • http://czdashan.cn/uploadfile/file/2021051005505773499.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/c6c9d4ba2f7f811f48c1352b3f542f53/xidukepegisatesegof.pdfIn PDF document text
    • http://abnicum.com/files/file/44083334633.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5aa150f50---90230793185.pdfIn PDF document text
    • http://pampa.be/uploads/userfiles/files/nudonuke.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ca31108f537---27318100652.pdfIn PDF document text
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3b42471b20---botejopixixefitu.pdfIn PDF document text
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/160bf698dc80e5---81899919696.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/5ut06pb29tnfmbqbo2s4830emn/41807058281.pdfIn PDF document text
    • http://logtech.cz/foto/Image/file/denujewakuw.pdfIn PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/tbh8c65298crgtdk26konads3p/35792198084.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/bedef5ab49f76f52bf63fbbab64fb153/jipex.pdfIn PDF document text
    • http://valkexclusief.reviews/app/webroot/files/userfiles/files/81885963233.pdfIn PDF document text
    • http://upoart.com/ckfinder/userfiles/files/45457140477.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/4f780185223ddf4eb02c33dd1111182d/85797645102.pdfIn PDF document text
    • http://allasclub.com/campannas/file/61371409426.pdfIn PDF document text
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/f7c9ao0ro25d5fuptabqc3hos7/48888491810.pdfIn PDF document text
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/9inn4fuvevlok14t5oqsase2mq/suliregu.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/408504de51c80e0558bf292e260c4a3b/20113541937.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=harrod+domar+model+of+economic+growth+pdfPDF 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_off0000ead2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAD2 19236 bytes
SHA-256: af271451afeb64b3163c134e6500e4b3ecd8cf430b919688fc1e2fb55c00ce34
font_01_sfnt_off00011d06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D06 10976 bytes
SHA-256: d8b995d3194043102ba03e58c5af69c7000897e5297ac6a1373dca6891d68c97
font_02_sfnt_off00013611.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13611 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1