Malicious PDF — malware analysis report

Static analysis result for SHA-256 b87b2c6391c2e4b0…

MALICIOUS

PDF

69.1 KB Created: 2021-09-27 10:44:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 33804fdf660e4316d5dffe4b3d6d7805 SHA-1: c3275f7aef8822c31b0c6e0b9ccc46cab2a0e10d SHA-256: b87b2c6391c2e4b07445ef22b70a5b37c18aeb3019f3b26ea66d9c2bd8a818f4
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with several links pointing to compromised CMS upload directories. The file's purpose appears to be directing users to potentially malicious content through a network of links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

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://2018.letnifestiwal.pl/ckfinder/userfiles/files/jemekepatox.pdf In PDF document text
    • http://cungcapbaoduongcuanhatban.com/upload/files/48291481940.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614e41cd961b4---melovak.pdfIn PDF document text
    • http://mudrberanova.cz/userfiles/file/57726566993.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614dbaccb4068---3601295882.pdfIn PDF document text
    • https://martas.vodrsport.cz/uploads/files/tefejopaxinexopetexov.pdfIn PDF document text
    • http://www.anieliasfx.com/uploads/textareas/file/wararoxikewisi.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/72547203769.pdfIn PDF document text
    • https://archielectronics.com/userfiles/files/66563467937.pdfIn PDF document text
    • https://wickedcheesy.com/images/file/lolunifalivenujatada.pdfIn PDF document text
    • https://ecpa.fr/uploaded/file/54372604232.pdfIn PDF document text
    • http://gwynnoak.abwingsmd.com/uploads/files/gurawumurubaparezavikazuw.pdfIn PDF document text
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/df20da038d942f2ca75792c5e2b09343/nukopawitotakad.pdfIn PDF document text
    • http://learnazia.com/fck/imagesfile/98287729561.pdfIn PDF document text
    • http://aqcorth.specialty-match.com/upload/files/97459892080.pdfIn PDF document text
    • http://ctm.it/userfiles/file/tamelilebosevefut.pdfIn PDF document text
    • https://tradingcall.in/ckfinder/userfiles/files/82443678605.pdfIn PDF document text
    • https://nulifeus.com/~nulife/userfiles/file/sofemenamelukuroxuv.pdfIn PDF document text
    • https://videoeffect.ir/data/file/figifefarupib.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/skrd19um59eqc9ith6ppquhn1m/77150727272.pdfIn PDF document text
    • https://pasarantogel2.com/contents/files/zifat.pdfIn PDF document text
    • https://opsclown.it/ckfinder/userfiles/files/tuririwotegunijuzuf.pdfIn PDF document text
    • https://www.adoz.cz/ckfinder/userfiles/files/buvotesekuwovatu.pdfIn PDF document text
    • http://heldermusic.nl/ckfinder/userfiles/files/46930477613.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=best+cgi+app+for+androidPDF 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_off0000af1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF1D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c734.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC734 10804 bytes
SHA-256: 8a6bc55206332c92f4d842024b835448cd166e0006fd9dad4eb9947dd678d3fd
font_02_sfnt_off0000e00b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE00B 15156 bytes
SHA-256: 9f139a1633f97503dbe67291edfb0ced4bbdc2412acfdeeee2b3bc2557a5dbc1