Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf872c998b1d87f1…

MALICIOUS

PDF

86.1 KB Created: 2021-09-02 13:07:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 91cbd74148dadedb711a7471fa09053b SHA-1: 1cd51b6cefd89c05cf94e93a5cf8b778c3dd3125 SHA-256: bf872c998b1d87f1de5adfcd93d8d311542e14bf8b2a607bdf4bdf764b99da1f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting a link farm or phishing lure. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c715a30e0fd---81023870626.pdf
    • http://www.nowsingapore.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/1607e28be73b94---lebikafatigiforosuxovi.pdf
    • http://offerseir.com/basefile/offerseircom/files/forimijazurugekoda.pdf
    • https://www.hs-hofgastein.salzburg.at/ckfinder/userfiles/files/82007116296.pdf
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/huh97pomoen4k05hbbqp6gqlv2/rupokerila.pdf
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a7d99e8993c---weligizuzemol.pdf
    • http://nbpcpentecostalchurch.com/clients/65183/File/70553120535.pdf
    • https://incoyun.com/calisma2/files/uploads/wopufur.pdf
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160cda7658ee3c---jekevosigoripo.pdf
    • http://bezpieczna-strefa.pl/wp-content/plugins/super-forms/uploads/php/files/0920efacb1267c1890c756531f8bdaa3/13100325376.pdf
    • http://mackielaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/demowajanufezewovapujove.pdf
    • https://playerpress.com/ckfinder/userfiles/files/7673258860.pdf
    • http://music-saikung.com/ckfinder/userfiles/files/jewixageva.pdf
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/9oinplnq6c92ito918tmskavsj/19805754236.pdf
    • http://mindatpeace.us/uploads/files/34217033501.pdf
    • https://aarhuskortet.dk/images/file/zawumenasa.pdf
    • http://hoteldazegliotorino.com/userfiles/files/jubede.pdf
    • http://1-cx.com/ckfinder/userfiles/files/sapemem.pdf
    • http://cuahuyhoang.com/media/ftp/file/75296215685.pdf
    • http://timnhanhonline.com/upload/files/74098117375.pdf
    • http://odesignlab.ru/admin/ckfinder/userfiles/files/modanofetitozi.pdf
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a7a2dfaadb9---15240077232.pdf
    • http://orderkai.com/uploads/files/87238258440.pdf
    • http://topenglish.sk/app/webroot/gallery/files/65280562586.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fdf140ca8fe---66723309365.pdf
    • http://brno-skoleni.cz/ckfinder/userfiles/files/66846609927.pdf
    • https://paroles-vives.com/ckfinder/userfiles/files/bomabuleju.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=4th+grade+borrowing+math+worksheets
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e8ad.bin
cfe26099c8eaf817a6a663801cf3b34f4cfd656280ebb6b54f312e35c4d7bc32
pdf-font-stream PDF embedded font (sfnt) at offset 0xE8AD 10948 bytes
font_01_sfnt_off000101b3.bin
069b12d331000e97845eb29c78e18664acb997c8b520685f57f1e4c3796e0017
pdf-font-stream PDF embedded font (sfnt) at offset 0x101B3 17968 bytes
font_02_sfnt_off00013082.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13082 16792 bytes