Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef418473bc26c7db…

MALICIOUS

PDF

67.5 KB Created: 2021-09-27 01:45:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 483430c5744c817cd64a9a2f545b250f SHA-1: 29857ec916e8f6ee43f06b749d0b646898f5d8fe SHA-256: ef418473bc26c7db0fbb61800f6503509a7ccb14685c13b380a9f812750cb0a4
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on disposable domains or compromised CMS upload storage, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://panama4d.com/contents/files/lidal.pdf In PDF document text
    • https://detectagsafety.com/ckfinder/userfiles/files/guloguk.pdfIn PDF document text
    • http://klsele.com/userfiles/file/1632636078.pdfIn PDF document text
    • http://gimnazjum-krasiczyn.pl/img/userfiles/file/5427487535.pdfIn PDF document text
    • http://influences-vegetales.eu/assets/Image/files/29974437120.pdfIn PDF document text
    • https://alrukn.co/userfiles/files/81836379164.pdfIn PDF document text
    • http://coimbrasoftware.hu/images/uploads/files/gawilotovul.pdfIn PDF document text
    • http://ms-beauty.com/ckfinder/userfiles/files/luvagulatomuv.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/64dpl1d12mdhe3n9rcnrkeqq87/zuworitotevavifisenigabim.pdfIn PDF document text
    • http://0975811252cool.linker.tw/files/rorare.pdfIn PDF document text
    • http://thsport.dk/ckfinder/userfiles/files/guburad.pdfIn PDF document text
    • http://chikatere.com/Upload/files/godatezepubibog.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137c9789af22---pobikusibemasutug.pdfIn PDF document text
    • http://slstudio.it/userfiles/files/47709439962.pdfIn PDF document text
    • http://obrienbuilders.com/userfiles/file/wolakutaruwolaze.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16139db2f5f07f---99386340736.pdfIn PDF document text
    • http://kanoonkaraj.ir/dbmanager/filebank/htmlgallery/file///numixopibobefexagov.pdfIn PDF document text
    • http://soles2walk.cz/data/file/jipusu.pdfIn PDF document text
    • https://net-mex.hu/ckfinder/userfiles/files/puxewazilibevelawinibuto.pdfIn PDF document text
    • http://merlegdoktor.hu/tmp/jiwopegikerolofuki.pdfIn PDF document text
    • https://cortopolis.ar/userfiles/file/18891062898.pdfIn PDF document text
    • http://gld-lining.com/user_img/files/28547154855.pdfIn PDF document text
    • https://fiscconsulting.com/userfiles/file/kupekuzelubu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=bricks+breaker+hack+apkPDF 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_off0000ad35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD35 10388 bytes
SHA-256: e9ed52a5b3859db5ecbd000a7c1771048157113976c3cecfd3e13da32f3a271d
font_01_sfnt_off0000c4a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000dcb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCB8 14572 bytes
SHA-256: e55587507505a43ce397b2eea5e29195c043f351f430ad7ae9035bd4216d3fce