Malicious PDF — malware analysis report

Static analysis result for SHA-256 8719970939bd8d9d…

MALICIOUS

PDF

75.7 KB Created: 2021-09-09 13:32:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: dc5bf105aaa110beb9ab7b0464607334 SHA-1: 10cd06bbf752e3fbdb66c2acf7ec588d2ebc1e43 SHA-256: 8719970939bd8d9da85b711d0fa50d1ba7260f82f9abd4e62dd357cc53f89a66
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to potentially compromised websites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically highlights this behavior, suggesting an attempt to lure users to external resources. The presence of multiple unknown URLs, including one hosted on a compromised CMS upload directory, reinforces the phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132c26983fac---bojinafu.pdf In PDF document text
    • http://noahmission.org/dataroom/file/volarebawifedez.pdfIn PDF document text
    • https://stepweystudy.com/ckfinder/userfiles/files/38775761932.pdfIn PDF document text
    • http://zhizhencn.com/filespath/files/20210908001357.pdfIn PDF document text
    • http://nonstopsushi.com/uploads/files/gazasikaruruxujin.pdfIn PDF document text
    • https://intersat.lv/files/file/fotivadosujidimizomu.pdfIn PDF document text
    • http://carbontuning.ru/file/ribijujake.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/o9t7c9pjv5mpcj0blk39alui6c/60937007607.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/aqumif0n03tsfpus26d6qv0l21/lubolotida.pdfIn PDF document text
    • https://bodykneadstherapy.com.au/ckfinder/userfiles/files/91461479336.pdfIn PDF document text
    • http://xn--vb0b83rba554gca.kr/page_data/file/20210902134927.pdfIn PDF document text
    • https://minjar.mebel18.com/uploads/files/56824682096.pdfIn PDF document text
    • https://gulfcans.com/home/madarmun/public_html/gulfcans/images/bulk_images/files/64427170345.pdfIn PDF document text
    • http://ct-tci.com/cttax/userfiles/files/fiwefi.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/3dbf6e83c1557624c2fe1a45fb1beba1/68051173995.pdfIn PDF document text
    • http://puzynowska-kancelaria.com/userfiles/file/74402684559.pdfIn PDF document text
    • http://egitara.com/upfiles/files/2446134874.pdfIn PDF document text
    • https://bepxuyenviet.com/upload/files/69064666799.pdfIn PDF document text
    • http://keifo.ru/ckfinder/userfiles/files/61172733486.pdfIn PDF document text
    • https://thietbixaydungcantho.com/canthomobile2/public/images/sanpham/files/wadudaw.pdfIn PDF document text
    • https://serka.com/serka/upload/files/29261488880.pdfIn PDF document text
    • http://windowsplusllc.com/ckfinder/userfiles/files/tobejezukeposudeb.pdfIn PDF document text
    • http://capitaldanceacademy.com/userfiles/files/jomeki.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=programming+problem+solving+and+abstraction+with+c+pdf+download+freePDF 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_off0000bfb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFB6 11360 bytes
SHA-256: b4bd29350383af65604bb04f1af9aa69f59ca66d6c3a7672068ceeff27837d7c
font_01_sfnt_off0000d9e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9E8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f1fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1FA 18504 bytes
SHA-256: 7c31140d0a6cbbf74561ac6c45a47556f6c5602665cbf784a64cc58d4d5ff190