Malicious PDF — malware analysis report

Static analysis result for SHA-256 9883566df258a871…

MALICIOUS

PDF

70.4 KB Created: 2021-09-25 09:46:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: b242a8923d8df1db49ac6d92c15372f5 SHA-1: b61def9912cf6a3d072a8c6e523eeceb92c2a050 SHA-256: 9883566df258a871ee8525774a553c7e171f7be286516071f6618021cbcb1763
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to lure users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a phishing or credential harvesting attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://philabc.ru/uplcv?utm_term=reverse+percentage+increase PDF link annotation
    • http://szerecsengyogyszertar.hu/editor_up/46109965926.pdfIn PDF document text
    • http://softwaretesting.kr/club/data/userfiles/file/20210905030707.pdfIn PDF document text
    • https://audreyheselmans.com/_files/file/68371237562.pdfIn PDF document text
    • http://portalinmobiliario24.com/uploades/fckeditorfile/jerosuxirunorem.pdfIn PDF document text
    • http://ginzaoakland.com/uploads/files/87189439236.pdfIn PDF document text
    • http://www.ppk-kp3k.kkp.go.id/ver2/extra/ckfinder/core/connector/php/media/ckfinder/files/39675675920.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140939148e73---gajut.pdfIn PDF document text
    • https://jasz-pap.hu/UserFiles/file/41301366280.pdfIn PDF document text
    • http://gidaero.com/upload/fckeditor/file/30941458669.pdfIn PDF document text
    • https://thefertilizerequipment.com/d/files/32206321464.pdfIn PDF document text
    • http://www.sictombbi.fr/ckfinder/userfiles/files/73574319318.pdfIn PDF document text
    • https://baoholaodong24.com/userfiles/file/73835149052.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/1613287a78ddc5---48026349391.pdfIn PDF document text
    • http://vanharteyoga.nl/uploads/files/47480227151.pdfIn PDF document text
    • http://dxczx.com/ckfinder/userfiles/files/20210918_081728.pdfIn PDF document text
    • http://testplanet.nl/uploads/files/71803106107.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/4evd5pc7ra6o2nfg2nga0dfeiu/38452534960.pdfIn PDF document text
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/d8e57632103720922cb132720ef8e245/32610092336.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/55577f5dfa64df36b2f6734675b76689/33468415260.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c307724ed1---65742734055.pdfIn PDF document text
    • https://soccerauquebec.com/userfiles/file/9278036330.pdfIn PDF document text
    • https://bike-accessories.supersites.gr/content/ckfinder/files/felen.pdfIn PDF document text
    • https://snoman.mb.ca/ckfinder/userfiles/files/57058509629.pdfIn PDF document text
    • http://espaciocultivarte.com/ckfinder/userfiles/files/70890726712.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_off0000b3d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3D2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cbe9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBE9 10496 bytes
SHA-256: cd87a9031b13e7770393a1a9b6f2e443836793532ff61bad5f9cce6524d4cb59
font_02_sfnt_off0000e3f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3F4 15700 bytes
SHA-256: 688cc11f358ae69187c670a087380a0001dbfde16745764711a84746e7c6fd7d