Malicious PDF — malware analysis report

Static analysis result for SHA-256 d6d7b979cae45339…

MALICIOUS

PDF

84.5 KB Created: 2021-06-30 09:37:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: a3b378a409fea4e964e0426787ea712e SHA-1: c78d9de5a0727fa34731b3eb2554da01ced3ac55 SHA-256: d6d7b979cae45339bdaf69ad64c1469d0e60fdd0fc66161829a7a1632bf13516
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with numerous URLs pointing to compromised WordPress sites and disposable hosting, suggesting a phishing or malware distribution scheme. The document body is unreadable, but the presence of external URIs and link farm characteristics strongly suggests the file's purpose is to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://synerhu.ru/uplcv?utm_term=science+question+bank+class+10+pdf PDF link annotation
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b386de69192---pebiz.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606f7a772b579---peseduluxiwor.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/16077cab516d96---sojijuwagunuloz.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/f3e637784f938d9315d396a0e193824d/95197270051.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/6b326dc8a653d2f67f7c890fc3d73cf1/jukizukilagufekerap.pdfIn PDF document text
    • http://millecolori.it/images/file/60094265834.pdfIn PDF document text
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/2gqro0mbrrpsip1r73ue4aeula/73864589885.pdfIn PDF document text
    • http://nuestratierrapremios.com/campannas/file/55675838891.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16076c4f31bc7a---39761262691.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/16089f115746d5---43861770794.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a9de96e1cb4---27112880373.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/160911f150f1c9---zatesu.pdfIn PDF document text
    • https://yz-yongzhong.com/upfiles/editor/files/zipedetivagovus.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/963daf4a267ac320ca2e8abf41720712/22910064214.pdfIn PDF document text
    • http://sva-jeanroze.com/xmedia/file/tipopin.pdfIn PDF document text
    • https://myupfield.link/wp-content/plugins/super-forms/uploads/php/files/o4vpgfm5thk1tu2larq837v2gn/digabalik.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/sgei1ml00t2ocomhe4c5l4eb85/17332891951.pdfIn PDF document text
    • https://ambientltg.com/wp-content/plugins/super-forms/uploads/php/files/dfaa398baca21e8239f92df17803b93c/78639353291.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1609a666fec88a---2402962142.pdfIn PDF document text
    • http://b-solutions.net/userfiles/file/jubixavufemesuruxekife.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d060d1e298e---55261567270.pdfIn PDF document text
    • http://msamerica.net/clients/873634/File/ditonejomobuba.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b98f98a070---jelozejagezap.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/bf5138f3165a1b260ee5383d5a441d6a/26374683516.pdfIn PDF document text
    • https://bnovum.hu/downloads/78746288062.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_off0000e493.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE493 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fca5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCA5 16944 bytes
SHA-256: 84c7077a348c189cbc9fb8cf32f6c8fc1260e49440620d893abdf9f2a47d9d17
font_02_sfnt_off000128db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128DB 11240 bytes
SHA-256: 6b9120e0fbf6042d81351445f36daddcc0946dd1918722ba92b9b744fbf98de9