Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c12a21fc268e5e9…

MALICIOUS

PDF

75.5 KB Created: 2021-09-16 15:07:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 0a768e300ae88a8fc7c94c8400935867 SHA-1: 76159f17f33e648b6452a4d3325e2f73be087c9f SHA-256: 5c12a21fc268e5e9e6558ed3ca50740922068fb338909949c805d727e32fc5f9
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm or SEO spamming operation. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lure users to malicious content or phishing sites. The document body is unreadable binary data, providing no direct clues to its purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://partiaweb.ir/upload/files/zukovupilo.pdf In PDF document text
    • https://goez3.com/10005001208290177/ckfinder/userfiles/files/suvusawitovofuvoniruze.pdfIn PDF document text
    • http://pc580.cn/upload_fck/file/2021-9-1/20210901132745391520.pdfIn PDF document text
    • https://mayxaydungthienlong.com/uploads/files/files/59204542754.pdfIn PDF document text
    • https://riwg.in/userfiles/file/tatoxonemarerasubusari.pdfIn PDF document text
    • http://uptownherndon.com/uploads/files/rekuzizotevojim.pdfIn PDF document text
    • https://bompentax.com/quangbasanpham/app/webroot/upload/image/files/koxovusikanev.pdfIn PDF document text
    • http://srtcivilnorth.com/ckeditor_file/files/warev.pdfIn PDF document text
    • http://hoilhpnqbthanh.com/upload/file/rokilubopo.pdfIn PDF document text
    • https://ventadeterrenosurbanos.com/userfiles/file/finufuz.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161358f3c3cedb---takonox.pdfIn PDF document text
    • http://pileshoppen.dk/userfiles/file/towegenugurulovu.pdfIn PDF document text
    • http://stadtbild-intervention.de/Quansis/ckfinder/userfiles/files/97815525390.pdfIn PDF document text
    • http://elitakhealing.com/ckfinder/userfiles/files/mokotasudemabiniferudisaj.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/bdb8b562349f7c976cc90fd6a1d69873/xagaxaremogig.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614181a76597a---telixi.pdfIn PDF document text
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/21853771924.pdfIn PDF document text
    • https://fzclicks.com/demo/files/editor/file/95951112514.pdfIn PDF document text
    • http://bjyhyy.cn/filespath/files/20210904082538.pdfIn PDF document text
    • https://www.liftechforklifts.com.au/application/third_party/ckfinder/userfiles/files/32621516194.pdfIn PDF document text
    • http://tuclubcr.com/campannas/file/ralip.pdfIn PDF document text
    • https://nenmongdangquang.com/upload/files/51786402969.pdfIn PDF document text
    • https://sokolzgierz.pl/web/uploads/files/77182016244.pdfIn PDF document text
    • https://petpetmates.com/files/editor/file/ledezorexutazonodajamag.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=five+nights+at+freddy%27s+3+game+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_off0000c46e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC46E 10996 bytes
SHA-256: 42f90aa2abd804ff931137e82cc61e638fffb3f0a2447d69f1b26c9f168b3434
font_01_sfnt_off0000ddad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDAD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f5bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5BF 16500 bytes
SHA-256: d225e18f4106f119e27b2b9a85dce3785655369a439b98aefced4955bc12d64a