Malicious PDF — malware analysis report

Static analysis result for SHA-256 213303df4a53918e…

MALICIOUS

PDF

90.2 KB Created: 2021-09-18 13:19:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a8a71a783687355740bd96ddd2f7f77c SHA-1: 5748e04fe1c1d666905fa690b77ee4ebb7fd7ffe SHA-256: 213303df4a53918ee29ca7270e28f90a9daae30cb3cb79d161d59514ce2c88d2
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous embedded URLs, many of which point to suspicious domains, and one heuristic specifically identified it as a link farm on disposable hosting. While no scripts were extracted, the overall structure and heuristic firings suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9876

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://susta.vn/userfiles/file/pekejirufufipixosopefup.pdf In PDF document text
    • https://tese.in/ckfinder/userfiles/files/dopetodavoz.pdfIn PDF document text
    • http://thaoduocquyhiem.com/userfiles/image/file/xekuvamevakixudejarimav.pdfIn PDF document text
    • https://www.wemservice.com/ckfinder/userfiles/files/jivuzanolukuwaxaritin.pdfIn PDF document text
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/79992807511.pdfIn PDF document text
    • http://tentimesneedlehill.com/UPFILE/userfiles/files/bizumigekugepu.pdfIn PDF document text
    • http://www.premiumimport.nl/ckfinder/userfiles/files/xajerojofa.pdfIn PDF document text
    • http://flexinform.com/hirlevel/file/xepijup.pdfIn PDF document text
    • http://bretagne.annuaire-regional.com/ckfinder/userfiles/files/62919914117.pdfIn PDF document text
    • http://cornucopiafrederick.com/uploads/files/mowiw.pdfIn PDF document text
    • https://imihwa.com/uploads/image/20210912/files/20210912040218.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/171847158236.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/9e78d34c28498dd0468487e94fbe1f04/tezuxikixuvudezixidej.pdfIn PDF document text
    • http://yoron.net/up/files/bodebanesigaxededudekir.pdfIn PDF document text
    • http://anapro.com/ckfinder/userfiles/files/wibojezuruxikubuneg.pdfIn PDF document text
    • http://www.moyekolodin.com/files/daperesepuvar.pdfIn PDF document text
    • https://doluhosting.com/calisma2/files/uploads/wosetovibojelu.pdfIn PDF document text
    • https://hattoco.vn/images/ckeditor/files/sajetisuganozofilomoru.pdfIn PDF document text
    • https://shoppingplanet.cityplanet.ro/ckfinder/userfiles/files/48481264832.pdfIn PDF document text
    • https://xn--fct8ml6mwue.tw/uploads/files/27474685384.pdfIn PDF document text
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/61f7dd112b74600a6b799fae2f1e56ff/pomebemoputuvade.pdfIn PDF document text
    • http://yishiweb.com/upfiles/files/20210912_102107.pdfIn PDF document text
    • https://casaalu.com/luutru/files/mujafixanune.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=old+it+moviePDF 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_off00010101.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10101 17228 bytes
SHA-256: 1d759ffdc094bb0c14f8c824541e10154699c8c35099a1192c9f5556eca36d06
font_01_sfnt_off00012da5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DA5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000145bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x145BB 9964 bytes
SHA-256: ad5afdf463404c9e59c3d16cf03671c12bdb8c291e5c7e42d1834d589a021717