Malicious PDF — malware analysis report

Static analysis result for SHA-256 db241f188aa96dc8…

MALICIOUS

PDF

70.6 KB Created: 2021-09-16 08:08:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: a08a88da34c758668b6702c9c6ec211c SHA-1: 2cef8e3de733e3fccf2ebd1ec93ccdf850743d6b SHA-256: db241f188aa96dc876c63ecff90475f4031bf28ab506d83b811ba17513296bd3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery via embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://irlanc.ru/uplcv?utm_term=ssr+shadowsocks+apk PDF link annotation
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/fc7472161ffac43c65a188714f0e5b17/70934348449.pdfIn PDF document text
    • http://inercial.es/uploads/files/zavivevisusuxekoniw.pdfIn PDF document text
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/ca73b156501ca8eb6fe9f9c8c9c69202/nazotumuzutix.pdfIn PDF document text
    • https://markaoyun.com/calisma2/files/uploads/fuwezomuf.pdfIn PDF document text
    • http://ever0036.com/assets/uploads/ckedit/files/20210913063842.pdfIn PDF document text
    • http://www.toptehnik.si/images/76730771397.pdfIn PDF document text
    • https://soechi.net/userfiles/file/15645375679.pdfIn PDF document text
    • http://kmsenior.org/file/files/57375634497.pdfIn PDF document text
    • https://baptistfriends.org/media/34037526323.pdfIn PDF document text
    • http://www.naturhalles.fr/fckeditor/userfiles/file/93998987712.pdfIn PDF document text
    • https://samsungvrvklima.com/upload/ckfinder/files/83097175789.pdfIn PDF document text
    • http://otevrel.eu/ckfinder/userfiles/files/rewuzir.pdfIn PDF document text
    • http://lerucherdesanges.fr/userfiles/file/5315018042.pdfIn PDF document text
    • http://condominiobrisasdelnorte.com/userfiles/file/xuvulejozoziwuxezax.pdfIn PDF document text
    • http://bapassamarinda.id/assets/ckfinder/core/connector/php/uploads/files/didor.pdfIn PDF document text
    • https://yenhuy.vn/upload/files/kikuzuregabususorejojexi.pdfIn PDF document text
    • http://sculecuacumulator.ro/app/webroot/files/userfiles/files/14569957740.pdfIn PDF document text
    • http://boilerservis.ru/uploads/files/togemitupikaxaxoto.pdfIn PDF document text
    • https://girisimhaber.com/uploads/file/12760457824.pdfIn PDF document text
    • http://rc-modeller.se/images/file///2754596251.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131ad7002e6d---43004814047.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_off0000ae0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE0D 10392 bytes
SHA-256: 316035751495b4650dd0cbe2793c14914ef1f7c7924df50e0480bffd87dffb48
font_01_sfnt_off0000c5bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5BC 18576 bytes
SHA-256: 6d9188724d151f2fbad081b05558bc96d602511ba6956c7b0a51381c3b7cb516
font_02_sfnt_off0000f597.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF597 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1