Malicious PDF — malware analysis report

Static analysis result for SHA-256 135fd60335e6f64d…

MALICIOUS

PDF

78.9 KB Created: 2021-09-02 14:05:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 09012bb7434b7dbc3ea31f3f9610e339 SHA-1: 08bbfd6ab6bf24ef0632669ec237eb30c17c5af4 SHA-256: 135fd60335e6f64d35cada99914a1cbdcc26e57da3ee84bf6f563cd1841e6e4b
156 Risk Score

Malware Insights

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

The PDF was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The document contains a link farm pointing to multiple PDF files hosted on compromised WordPress sites and disposable hosting, suggesting a phishing or SEO manipulation campaign. No scripts were extracted, and the document body was unreadable, limiting further analysis of the specific lure.

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://arnetbilgisayar.com/upload/ckfinder/files/89873887491.pdf In PDF document text
    • https://knurussian.kr/DATA/upload/files/202108192058441974.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cabf85c734---76261501233.pdfIn PDF document text
    • http://dzbnf.com/upload/file///84628793711.pdfIn PDF document text
    • http://cupta.org/userfiles/files/20210616103446.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/cfsd2op1ncomkgvf03s922mou1/76403787158.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/f79cb2195644d9fab7447ab99e4ee6eb/jonumerikejepifajir.pdfIn PDF document text
    • https://athensviptour.com/wp-content/plugins/super-forms/uploads/php/files/15804c87cd685922fcca6384cd3e7f91/27369102810.pdfIn PDF document text
    • http://re-view.online/fckFiles/file/75623073722.pdfIn PDF document text
    • http://weiken-rc.com/upload/files/kamodemijo.pdfIn PDF document text
    • https://www.growxponential.com/wp-content/plugins/super-forms/uploads/php/files/fvs5dfd5krr9peea114gmnocka/noxekimafilefazurelo.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/1611fd5ce716a4---98347458746.pdfIn PDF document text
    • http://mrhobbscoffee.com/images/uploads/file/22113104832.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/160c7372dbcc4c---kojabikixapunememe.pdfIn PDF document text
    • http://globalone-mould.com/gbw/fckfiles/20210815040151.pdfIn PDF document text
    • http://espacioschillout.es/images/admin/file/78750734120.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/bef1c3f34614217035de54466b01eaad/golaxito.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160916d56d7172---momuzu.pdfIn PDF document text
    • http://anhopphat.com/uploads/files/39993483984.pdfIn PDF document text
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/16078cb046ec6c---9457445933.pdfIn PDF document text
    • http://wsmr.us/userfiles/file/83747844967.pdfIn PDF document text
    • http://sunwisechem.com/Uploadfiles/files/rujetupidadevamaxenazab.pdfIn PDF document text
    • https://dodatkireklamowe.pl/web/uploads/files/xafasuxejoman.pdfIn PDF document text
    • https://zoomkish.com/basefile/zoomkishcom/files/dolesinaniwemikirafakozub.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/4dc0d18255bed898ad8c8731f1c884dc/83156324561.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=basic+story+map+pdfPDF 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_off0000d008.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD008 10664 bytes
SHA-256: d1e40d6398a4bf6c606fb07815935e5c665518bbc9f0961619aad285f77b7561
font_01_sfnt_off0000e893.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE893 17476 bytes
SHA-256: 3bd70381662812724058400a4e189d8bbdb60dd6098c36be8d0572fbc09275ff
font_02_sfnt_off000115c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115C1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1