Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a133edb7373cf8e…

MALICIOUS

PDF

80.4 KB Created: 2021-09-07 21:07:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 283d4d3f4feba727fb56d51248ac0972 SHA-1: af618baf7cee93b84c441de5561cb21986ded6ee SHA-256: 1a133edb7373cf8e0be9e45af484bd69fc5b730d24a8da650ec4df4e10f67a10
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, specifically identified as a phishing or trojan distribution attempt. The document functions as a link farm, directing users to numerous external websites, many of which are hosted on compromised WordPress installations or disposable domains. The presence of multiple distinct hosts and the use of UTM parameters suggest an effort to obscure the ultimate destination and potentially track user interactions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://ketchas.ru/uplcv?utm_term=hp+proliant+dl380p+gen9+manual PDF link annotation
    • http://fcv-bo.org/data/fcv-bo/userfiles/file/pupesewetirorisitotu.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b55c00402ac---3462702133.pdfIn PDF document text
    • http://10glazsikeyrosa.ru/file/98490773326.pdfIn PDF document text
    • https://appchecar.com/ckfinder/userfiles/files/34035450739.pdfIn PDF document text
    • https://kaptenhoki.info/contents//files/31867378265.pdfIn PDF document text
    • http://thesnowmanicecream.com/ckfinder/userfiles/files/45595391170.pdfIn PDF document text
    • http://sanzmendia.com/userfiles/files/xeporifopebatarepo.pdfIn PDF document text
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/d32c5d4ea022e2142fccaca5f1902f2d/velolifagonerebago.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c02fa68d03c---48169854872.pdfIn PDF document text
    • https://law.com.sg/wp-content/plugins/super-forms/uploads/php/files/d9502c326c014b7e03183832fdcf088b/mufenugopomosara.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/vunimowujomisijudefak.pdfIn PDF document text
    • https://cevhertemizlik.com/userfiles/files/dogopu.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/2035dcf80c90169210d384e00c3769cf/pugupurubexudeli.pdfIn PDF document text
    • http://chukysovin.com/img-svc/files/dogikiduni.pdfIn PDF document text
    • https://www.mii.net/wp-content/plugins/super-forms/uploads/php/files/f37d2925f213f281fbb8146101ace9a2/tuxosenuwomolekojapek.pdfIn PDF document text
    • http://3e-recycling.ru/app/webroot/filesfiles/54700202781.pdfIn PDF document text
    • http://billagelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/kapomix.pdfIn PDF document text
    • https://weishinclinic.com/uploads/files/202108141408505610.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085c07d82c1a---kefabijazelulalomajezatus.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/5vp89tcpdod8rr7mgsfc5khfc0/39125822558.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1610c1f9ad2a18---19794346207.pdfIn PDF document text
    • http://puntolinea.org/userfiles/files/89048647159.pdfIn PDF document text
    • 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_off0000d2fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2FB 11328 bytes
SHA-256: 209b5f234573bef2c8e2a37a8f36b5f8123dc3385d929b9234fcf11605f2e4ef
font_01_sfnt_off0000ed4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED4B 18224 bytes
SHA-256: c652877fdb564bc67b05d09a31d5f8cfa278df4e4b8146523d3ccf5c150696f1
font_02_sfnt_off00011be4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BE4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1