Malicious PDF — malware analysis report

Static analysis result for SHA-256 a34b88c0a3b7f8a5…

MALICIOUS

PDF

97.5 KB Created: 2021-06-28 14:46:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 2e558cc90e2b2656d093e2d44fb55e09 SHA-1: c430993663dad91affa38e8b2759871bfca8bd93 SHA-256: a34b88c0a3b7f8a52677ecf3e234b104ef335a3d2d7310f8641f5450cff41e90
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised WordPress upload storage, with numerous distinct hosts and URLs. The document body was unreadable, but the presence of multiple links to potentially malicious sites suggests an attempt to redirect the user to a malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9806

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 https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/16093fd2f7bd66---4567624981.pdf In PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/e1ffb5c2206a3a231a28dd107b0d3e68/ginudatobijizelepominu.pdfIn PDF document text
    • https://koratspring.com/upload/file/vabutufazokugejuzobi.pdfIn PDF document text
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609a2ce5d4cb9---43818633462.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/441ddc99c653a931f2edb567770a1a32/tisip.pdfIn PDF document text
    • http://aite-materials.com/upfiles/file/janudenusesuxeti.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1607a3d188eb5e---vilanibefojagarexawape.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160ac1bdf06f03---pikunifekimutowo.pdfIn PDF document text
    • http://fullx.net/files/lufodival.pdfIn PDF document text
    • http://bitite.lv/media/txt/122/file/12598546412.pdfIn PDF document text
    • https://centrosteadycam.it/wp-content/plugins/super-forms/uploads/php/files/f21aa5c98e03dcd8c5032bc0f88289ac/nobazemomosuzanokenaz.pdfIn PDF document text
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/40f639030ff166cf587213ef52d257f8/limozaxo.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b42ce02ac37---5249727101.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/bi47nq6gccsn48074fvtpk4f9m/34476176211.pdfIn PDF document text
    • https://advantagelic.com/singhania/downloads/file/nobotumaxajapami.pdfIn PDF document text
    • https://nevisnews.com/userfiles/bolerada.pdfIn PDF document text
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/32f4f696322b195cca9de77e624df0aa/watimapexekupivawojadajam.pdfIn PDF document text
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/8bccc594c99b2790e1210521d23173d0/wimusepuzufiza.pdfIn PDF document text
    • https://autopratichesas.it/file/44013685552.pdfIn PDF document text
    • http://lex-ter.ru/admin/ckfinder/userfiles/files/25715686205.pdfIn PDF document text
    • https://groupunsur4.com/contents//files/dubasexiwi.pdfIn PDF document text
    • https://funkydrop.shop/wp-content/plugins/super-forms/uploads/php/files/8ffc0420c8d4ff94b5a66e65a8555644/78947073302.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6ec006bbbc---10451530364.pdfIn PDF document text
    • http://aylincinarli.com/fckfiles/file/donizabi.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/27ad583e396b50322625cc1502cd1c1a/35221372107.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a27656ce405---rigeboxoxonaxunitexosotiz.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/jimulikix.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=hot+new+reporterPDF 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_off00011d86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D86 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001359c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1359C 9856 bytes
SHA-256: 0a1b13d98f592062a223c30cfa706fc219513dda027597011638af54cc68f814
font_02_sfnt_off00014b5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14B5E 17860 bytes
SHA-256: 7b7b8b077b17752b4250bb05cf487ff384e850583cb26e7c1a3d2ea3a26b9c19