Malicious PDF — malware analysis report

Static analysis result for SHA-256 71b3e7f63c85f233…

MALICIOUS

PDF

76.8 KB Created: 2021-09-06 00:06:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: a6639787c5c8e070803d1285de9e5bde SHA-1: 70d38d46ea54d592d42d78918e1a93faad3d2c18 SHA-256: 71b3e7f63c85f23333b87636a223e20407a552ef5980681f3cb27865a4cfaf15
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised CMS uploads and disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The presence of multiple PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://m-co.de/wp-content/plugins/super-forms/uploads/php/files/mjpvh7df4d1qf383jqsq6of0qd/pesamulefoji.pdf In PDF document text
    • https://avukat.dnsaktif.net/upload/files/tivajobutuv.pdfIn PDF document text
    • http://vencedor.coop/images/admin/file/pevanutisemoz.pdfIn PDF document text
    • http://tythb.com/uploadfile/files/5858855965.pdfIn PDF document text
    • http://staceyasp.com/UserFiles/file/jaxodelep.pdfIn PDF document text
    • http://ilsogno-bomboniere.com/userfiles/files/kadowew.pdfIn PDF document text
    • https://fetogram.com/images/upload/files/67190134383.pdfIn PDF document text
    • https://kop-trans.pl/uploads/userfiles/files/nabugopujikagilubojakesi.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160face7d92acd---zapipizipozuvupujasa.pdfIn PDF document text
    • http://hotelamadeustorino.com/userfiles/files/latojagiwuvikexugutaret.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/914adf698987d624b2dc293a2fdbdd35/17605480426.pdfIn PDF document text
    • http://onsijsselstein.nl/userfiles/files/13486668229.pdfIn PDF document text
    • https://rockyshairsalon.com/wp-content/plugins/super-forms/uploads/php/files/dfc12h9cd63k7loc0p61ff69r1/zivavoguperarodowozogaz.pdfIn PDF document text
    • https://alrukn.co/userfiles/files/26310270130.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608990c794be5---kefodufamufajo.pdfIn PDF document text
    • http://daearesort.com/FileData/ckfinder/files/20210623_E9162C8CA34E14AE.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/72e697c224d5ad3913c43e1fdbb84d57/lugob.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16075aac90da9a---ratesaradimobukosodibavod.pdfIn PDF document text
    • http://jgbt.us/pds/userfiles/files/nobodafokinat.pdfIn PDF document text
    • http://100gastro.cz/soubory/files/zilamasawobenofozaduw.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/b126ddc30c9adbc2c31420895b2286e4/33872021275.pdfIn PDF document text
    • http://famillespourstarlight.ca/clients/a/a9/a9b42c05011d3bb27e7f7ec2ed30324f/File/kugixuzuz.pdfIn PDF document text
    • http://immodraft.nrw/images/architekten_agentur_images_/file/63906748788.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/riberikomikixafuwisanazix.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=gta+v+lspdfr+arrest+managerPDF 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_off0000c6c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6C6 17596 bytes
SHA-256: 9a7f9f9f201c1b2c88f432d72f5cd2d1164df6c093fe4d7dea283497360157a7
font_01_sfnt_off0000f4b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4B0 10736 bytes
SHA-256: 1d731d77fc6f1a7238b347e75d78a48eaf519d5496c1489c00f9e2a3d5c74588
font_02_sfnt_off00010d36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D36 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1