Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8e4a93a8965e23a…

MALICIOUS

PDF

77.2 KB Created: 2021-06-25 21:45:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 18f65eccbded8a0e85c89399594a0e92 SHA-1: 20c228b4b36f16e46b26df4c2e39c6e9eb885fc5 SHA-256: c8e4a93a8965e23a9b09fb9ea9d1f7820280fa0a5f435d6aa01a2b32824e14b0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan threat. It functions as a link farm, directing users to numerous external URLs hosted on potentially compromised websites or disposable domains. The presence of external URI heuristics and link farm detection rules strongly suggests the document's primary purpose is to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://smidgel.ru/uplcv?utm_term=class+3+english+workbook+solutions
    • https://mimpiindah1.com/contents//files/95330462171.pdf
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608bee0aca3c4---21722997068.pdf
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/lp9f35e10f81v7jukugte5ohhi/70594383724.pdf
    • http://luxcottage.ru/stroykamen/userfiles/files/78835513979.pdf
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1608cc076ecc64---19322498721.pdf
    • http://wjvanderheidedienstverlening.nl/uploads/file/kimuzerek.pdf
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099f033d1938---83660147031.pdf
    • http://penzionklara.cz/userfiles/file/73043005451.pdf
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/b2f2ad17f9640b1554395e24e3e4c09a/xawiwexo.pdf
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/5362a3f9454568977f5a8bdce41135ca/dibowomajigiku.pdf
    • http://airconbank.com/upload/fckeditor/file/mudivitelerirusi.pdf
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/4gio3jm4hb64alidd22tpg6k4r/novonowujegepafasafefa.pdf
    • http://duoctruongxuan.vn/userfiles/image/file/92769304328.pdf
    • https://argentinaproduct.com/ckfinder/userfiles/files/zarixiperuzibijujodetaf.pdf
    • http://www.deopendeur.org/imgUser/file/mubazaloromik.pdf
    • http://evpltravel.com/xv_image/file/55542508116.pdf
    • http://sinhorelli.com/userfiles/file/83568576495.pdf
    • http://creative-format.com/upload/editor/files/71599053502.pdf
    • https://jotekonybakterium.hu/userfiles/files/88906717234.pdf
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1609854f697de9---45050564047.pdf
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bf68677218---gimopixosabi.pdf
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a228d69bd94---85455431437.pdf
    • https://morethancleaningservices.com/wp-content/plugins/super-forms/uploads/php/files/86b8912a6f5a5d1889d2aad407fdc948/madibigimixitodubevozax.pdf
    • http://staging.impactredevelopment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082040f0f8ad---bujitegapazu.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_off0000c8e6.bin
367f5bd7f63941c26e4c245a8ce5b5dc7dc78c20f2370fa7007181176d99da00
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8E6 16664 bytes
font_01_sfnt_off0000f43c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF43C 16792 bytes
font_02_sfnt_off00010c53.bin
316614255cb7d58e64b7342ec7b05f47381ef92cc11f74aeb65ea45471d5d696
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C53 11008 bytes