Malicious PDF — malware analysis report

Static analysis result for SHA-256 71220a9a93d5c422…

MALICIOUS

PDF

70.3 KB Created: 2021-10-08 17:06:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: b64fdd2d568562590afa1affed42498a SHA-1: 3744dc4b5de67a0303e46e27e9a01c47c5cbea9f SHA-256: 71220a9a93d5c422396024e7c434f8636c484fda8f99d70dd9fee74b2553db1c
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for exploiting PDF viewers. The PDF also contains numerous external URIs, many of which point to suspicious domains and appear to be part of a link farm designed to obscure the true destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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
  • 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 http://garagehayashi.com/js/upload/files/fipavobimipururumiduju.pdf In PDF document text
    • http://myphamlulanjina.com/upload/files/69055955386.pdfIn PDF document text
    • https://artasedanasingaraja.com/uploadfck/file/39701901686.pdfIn PDF document text
    • http://krukewittfarms.com/userfiles/file/46631099656.pdfIn PDF document text
    • https://vrindaindia.com/php/joseph/uploads/file/97570510376.pdfIn PDF document text
    • https://www.auto-ecole-rive-droite.fr/ckfinder/userfiles/files/wuwilitewumolike.pdfIn PDF document text
    • http://tauben-buchmeier.de/kleinberliner-schuetzen/userfiles/files/42615112297.pdfIn PDF document text
    • https://wmu24.ru/media/file/16930581933.pdfIn PDF document text
    • http://ramenhajimetustin.com/uploads/files/ruwuvalapefutun.pdfIn PDF document text
    • http://pharmabiosolutions.com/filespath/files/20210928111227.pdfIn PDF document text
    • https://databaze-zdarma.cz/userfiles/files/bajanev.pdfIn PDF document text
    • http://richmediahouse.com/admin/uploads/file/92423446720.pdfIn PDF document text
    • https://daks-96.com/f/uploads/files/nuvinotanalunegotovudupuz.pdfIn PDF document text
    • http://kdsonline.org/userfiles/file/mejuvujimoxoxin.pdfIn PDF document text
    • http://malabarisproducoes.com/arquivos/files/84044744561.pdfIn PDF document text
    • https://www.leadercaravans.com.au/application/third_party/ckfinder/userfiles/files/67005901208.pdfIn PDF document text
    • https://www.pepinieres-gey.fr/ckfinder/userfiles/files/sisepebuliv.pdfIn PDF document text
    • https://allianztc.ro/files/file/91208140781.pdfIn PDF document text
    • https://portalbime.com/UploadedFiles/New/file/dikitezusifexigefazorab.pdfIn PDF document text
    • http://cosyromania.com/media/file/wuxabakonegijekalovezev.pdfIn PDF document text
    • http://studio-castiglioni.com/userfiles/files/degubitasurasikafesanevoj.pdfIn PDF document text
    • http://edwardfmcgintypa.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/53386719071.pdfIn PDF document text
    • http://app0.linkeo.it/ckfinder/userfiles/files/wegoluvotelevupurixa.pdfIn PDF document text
    • http://geometramaurotozzi.it/userfiles/files/56020716586.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=geotechnical+engineering+worksPDF 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_off0000b195.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB195 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c9ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9AC 10724 bytes
SHA-256: feb2e14fd1a5f786a6337e709e859bf8466937fadb154597542a6be1661ae87b
font_02_sfnt_off0000e25a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE25A 16416 bytes
SHA-256: c73f763b6d0685bb851ed341cc3682d685f1367407aa65fc624c420d82934874