Malicious PDF — malware analysis report

Static analysis result for SHA-256 85253b5740eb445a…

MALICIOUS

PDF

82.2 KB Created: 2021-09-10 23:49:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 5cf9765ec729dc26ed88392082d204e5 SHA-1: d940c6dfb041d206f0c4a43adb7130a6384a2ee3 SHA-256: 85253b5740eb445a41a22da2b346b4a84e79d91cda8fbb962eebf428b50de96e
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains embedded JavaScript and a large number of external URIs, many of which point to disposable hosting and are likely used for phishing or distributing further malware. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript is likely responsible for redirecting the user to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://crysiq.ru/uplcv?utm_term=index+of+paid+apk PDF link annotation
    • http://www.dogwoodagility.nl/ckfinder/userfiles/files/biderufebewu.pdfIn PDF document text
    • http://vietdubai.com/userfiles/file/92949259292.pdfIn PDF document text
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/73355fbd81ce6896f90a722ce7146f26/24787532844.pdfIn PDF document text
    • http://akekaluck.com/ckfinder/userfiles/files/5078909471.pdfIn PDF document text
    • https://shidoremicrosys.com/media/kuxuvopixubagetimuxujon.pdfIn PDF document text
    • http://emanuelarombiarchitetto.eu/userfiles/files/77558996865.pdfIn PDF document text
    • http://archiw.gbpopatowiec.pl/img/upload/files/8724140095.pdfIn PDF document text
    • https://pamukoglu.com/userfiles/file/45458134111.pdfIn PDF document text
    • http://jadever.vn/Images_upload/files/timegesuxo.pdfIn PDF document text
    • https://satuldelut.ro/ckfinder/userfiles/files/79685311513.pdfIn PDF document text
    • http://christschoolblr.in/userfiles/file/wevisuxadofix.pdfIn PDF document text
    • https://tyeetomsfishing.com/userfiles/file/vizuvezeluwaf.pdfIn PDF document text
    • https://ajur.rest/uploads/userfiles/file/zizekatezu.pdfIn PDF document text
    • https://charteriraq.ir/basefile/charteriraqir/files/wexezebumawa.pdfIn PDF document text
    • https://raiporjai.com/piceditor/file/66795549054.pdfIn PDF document text
    • http://nilesk.com/userfiles/file/51712777053.pdfIn PDF document text
    • https://unicorn.mn/js/ckfinder/userfiles/files/revuvakivuropolir.pdfIn PDF document text
    • https://rasathantrananotech.com/ckfinder/userfiles/files/dinijiluwelovozamifazetij.pdfIn PDF document text
    • http://agapetown.net/ckfinder/userfiles/files/30714753044.pdfIn PDF document text
    • https://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/161353e9b4c25b---43094906820.pdfIn PDF document text
    • http://thamcohoaian.com/webroot/img/files/tutatapupuxojarurezaj.pdfIn PDF document text
    • https://sunkamalzemecilik.com/userfiles/file/21896648027.pdfIn PDF document text
    • https://aykutemlak.com/upload/ckfinder/files/29705704062.pdfIn PDF document text
    • http://balmybnb.com/t/tutorfirm/uploads/ck/files/lubamulowodirug.pdfIn PDF document text
    • http://melabo.com/upload/files/89792766295.pdfIn PDF document text
    • https://ostrichpharmaceuticals.com/userfiles/file/labitotijo.pdfIn PDF document text
    • 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_off0000dcde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCDE 18204 bytes
SHA-256: 93e01a944f9b678ef787fc0737cb4f02b716a4af13d592341c6209fd1e55c13f
font_01_sfnt_off00010c73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C73 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001248a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1248A 10224 bytes
SHA-256: 9e83bd951b70e560fcfdddd73873332a713df7fc6b7c9c26cd5384ab0fccbd0f