Malicious PDF — malware analysis report

Static analysis result for SHA-256 718d756a42470b82…

MALICIOUS

PDF

86.7 KB Created: 2021-07-25 13:22:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: fb718e6c64415cdd22e11e37f507bad6 SHA-1: cbe51386b9a149190d52df6a3a0bd14c6521c768 SHA-256: 718d756a42470b824091fd5c2c768cef14f5f954be38137933f6d982193ac62c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a vehicle for these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 http://marketherballize.com/ckfinder/userfiles/files/kivir.pdf In PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/sivavujojiwatanobunofosa.pdfIn PDF document text
    • http://www.vikingmaterials.com/img/xovujipam.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d629ad71b4---ketudazivukagedaropasemu.pdfIn PDF document text
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/bdf9dc783ef0eaf76458bfa8cae335c1/selesidaxevaki.pdfIn PDF document text
    • http://shmountaineering.co.uk/wp-content/plugins/super-forms/uploads/php/files/3lu7af50k04u75uq2s4sv93hm1/44488405867.pdfIn PDF document text
    • https://music-group-store.com/upload/files/notabedu.pdfIn PDF document text
    • http://odpadykj.cz/UserFiles/File/xibipobewagureropisufised.pdfIn PDF document text
    • http://monkey-do.net/userfiles/file/25608573193.pdfIn PDF document text
    • http://zaragozalawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/13938370418.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074d2204c2dd---95198554158.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1609430742e8b4---35729885360.pdfIn PDF document text
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/256650c488edf52b19af811fbd5030e7/47473812862.pdfIn PDF document text
    • http://thebellingerfamily.com/clients/0/05/05034faaa501c69409a7459485cba135/File/fogawaliwipoda.pdfIn PDF document text
    • http://beiks.info/public/file/gonanuzozibox.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f7535120708---retiwetifuzime.pdfIn PDF document text
    • http://merklink.nl/site/data/ws/files/pobuna.pdfIn PDF document text
    • https://kidneystonetreatment.in/userfiles/files/64202281710.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///puxuwevemofodasopaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=tactics+greg+koukl+dvdPDF 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_off0000eb8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB8D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001039f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1039F 18068 bytes
SHA-256: f4f1fb8822a5b01a86b1b57cc0be9fd5e9aa4586d46cd16055a3db558724d61a
font_02_sfnt_off00013327.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13327 10660 bytes
SHA-256: 3e72a1a11376c48336496800e3f7eb3f31936be330a588863315c1effc0e3d22