Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d668d8f078106e0…

MALICIOUS

PDF

69.5 KB Created: 2021-10-02 16:11:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 82394c0fd498d168ca4fa6a043ce4119 SHA-1: bb6f283f8c90a2e25f09dd827aa20fedc4d2e41c SHA-256: 3d668d8f078106e03ef91fe81bf7623b229c71c4a3c24db19a4ff826f72cc9e0
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous external URLs, many of which are hosted on compromised or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple links on potentially compromised CMS upload directories suggests an attempt to obscure the true destination and evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://war-old.its.vn/new/userfiles/file/7037013407.pdf In PDF document text
    • http://archidaldegan.eu/userfiles/files/foxiwapoxoti.pdfIn PDF document text
    • http://eegbiofeedback-leszno.pl/userfiles/file/93529396172.pdfIn PDF document text
    • https://drlalashow.com/php/billboard/uploads/file/48875332761.pdfIn PDF document text
    • http://go-trec.com/wp-content/plugins/super-forms/uploads/php/files/25fajkr6viv330scd6k4rifief/15862181058.pdfIn PDF document text
    • http://capesociety.ca/uploads/files/sikop.pdfIn PDF document text
    • https://lifo-sea.com/ckfinder/userfiles/files/53382278262.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/77409308667.pdfIn PDF document text
    • http://baocaosudanang24h.com/uploads/image/files/xekisikoserefaforomupi.pdfIn PDF document text
    • http://chpcentre.com/files/file/jikukuvuwaxawazuwiz.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/remknac6n0atf8bt4mv3t8ubre/53252004573.pdfIn PDF document text
    • http://kripasec.com/userfiles/file/vobulazonesasu.pdfIn PDF document text
    • https://tucarrorentacar.co/ckfinder/userfiles/files/xibodemalajun.pdfIn PDF document text
    • http://schuetzenfest-hemeringen.de/ablage/userfiles/files/topifidogududur.pdfIn PDF document text
    • http://amunt.madteam.net/ckfinder/userfiles/files/dufaxosogujo.pdfIn PDF document text
    • https://marblobaths.com/app/webroot/img/files/zezogijatajelazerupefuvif.pdfIn PDF document text
    • https://afritransport.com/app/webroot/files/file/fatezeno.pdfIn PDF document text
    • http://kbidc.kr/upload/editor/file/1631757910.pdfIn PDF document text
    • https://un7un9b3rl1pa7-99.com/contents/files/7128094833.pdfIn PDF document text
    • https://beaszemin.com/files/33180704286.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/82bmhepq4htv9562g75u2qe6sh/nasetibi.pdfIn PDF document text
    • https://stmpallet.com/ckfinder/userfiles/files/83210492314.pdfIn PDF document text
    • http://nkmate.com/FileData/ckfinder/files/20210922_885EAEABEE2B1871.pdfIn PDF document text
    • https://thefertilizerproductionline.com/d/files/74683675152.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=leadership+in+times+of+crisis+pdfPDF 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_off0000b25a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB25A 10796 bytes
SHA-256: 616e872ab6a47c62ea024b637c0c22ea6af264541ea7bcf348cbdc45a2baafb0
font_01_sfnt_off0000cafd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAFD 14684 bytes
SHA-256: 45fca90bbd80013205dacb799a485db17c98ed420c1eec4a0cd5a1874512bb4a
font_02_sfnt_off0000efcf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFCF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1