Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f3db987a680897c…

MALICIOUS

PDF

88.4 KB Created: 2021-08-01 08:01:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 35f056fdbda306a0a5cbf82b9f8fe712 SHA-1: 6bc13fab7bdaaffdf3d94296d29a34ea0eeeee45 SHA-256: 1f3db987a680897cd5fc7458cea34e6863398a83447004dc4cb9dd3243529372
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by multiple heuristics, including a high-confidence ML classifier and ClamAV detection. It functions as a link farm, directing users to compromised WordPress upload storage and other disposable hosting sites, which likely serve further malicious content or phishing pages. The PDF's structure and embedded URLs indicate a phishing attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc3b0bdef0a.pdf
    • http://vorne-sitzen.eu/pcms/content/file/8111447298.pdf
    • https://noithatkuongthinh.com/uploads/files/48629442086.pdf
    • https://medosojewellery.com/userfiles/files/ziwesujavinetil.pdf
    • http://donghozibistore.com/luutru/files/potutuvuworijoxojulaf.pdf
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afad0fe67a9---98655099151.pdf
    • http://bloomx.com/sites/all/sites/bloomx.com/files/70175251166.pdf
    • http://omni-links.com/images/blog//file/rajujos.pdf
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/7frpd7mc509rpdf8br8gu4q70v/weveda.pdf
    • http://auxerretv.com/content/public/file/27408181998.pdf
    • http://olddieselparts.com/ckfinder/userfiles/files/nixudigine.pdf
    • http://hiroshima-teishaku.com/userfiles/file/23162904723.pdf
    • https://gikguamerica.com/userfiles/file/fanapuvudiriz.pdf
    • http://ibiforstarlight.ca/clients/3/3c/3cfcca4e360ca8807b7dd7d6e7cbeae0/File/80380658414.pdf
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/2f48797ff7cb6c50ef1333f6a7fa96ec/ronutuvoz.pdf
    • http://jarosi.hu/files/file/64226886615.pdf
    • http://amandamaitland.com/images/file/ponedemazegedoxazanixidu.pdf
    • http://akkoryazilim.com/userfiles/file/2983103222.pdf
    • https://www.asahinafunnels.com/wp-content/plugins/super-forms/uploads/php/files/8v9vblhrnvqmsbe5lvi4c035v0/xulosaruge.pdf
    • https://dixietemporarystorage.com/wp-content/plugins/super-forms/uploads/php/files/b19ca0a76409a7b56c2749a286804007/pubipugakef.pdf
    • http://superazs.ru/images/news/file/88747973845.pdf
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160852870d50f0---tazagirom.pdf
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16088b682ab147---zuziba.pdf
    • https://svltv.in/userfiles/files/99315313669.pdf
    • http://ecoolteh.eu/galeria/file/82817625213.pdf
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a436854b71d---xuvuniputisuje.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=balboa+hot+tub+temperature+control+instructions
    • 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_off0000f25b.bin
cca6c247389535614dcba1c5bc4cc9b81c2e1f3df085f80d2335bcbd00fa45bf
pdf-font-stream PDF embedded font (sfnt) at offset 0xF25B 17968 bytes
font_01_sfnt_off000121e5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x121E5 16792 bytes
font_02_sfnt_off000139fc.bin
e93598aacb174ec426f6f795ead7780234fbb1db84aa1d98b7db7fe17543f713
pdf-font-stream PDF embedded font (sfnt) at offset 0x139FC 10932 bytes