Malicious PDF — malware analysis report

Static analysis result for SHA-256 fed1f4fc7f1089bb…

MALICIOUS

PDF

70.3 KB Created: 2021-09-25 18:55:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 40864f1890ab64d5db5deebca3f06342 SHA-1: 00e40fdbfe5aa68b80de238fb24ed4578cc7186e SHA-256: fed1f4fc7f1089bb6196e91f751ea9c663f018fde925a188e02c7a1572494c85
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, a common technique for executing malicious code within PDFs. It also features a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites, suggesting an attempt to obscure the final destination and evade detection. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 7

  • 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.
  • 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://www.serge-valentin.net/ckfinder/userfiles/files/xaxelikerop.pdf In PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/161343850c13f3---35227457796.pdfIn PDF document text
    • http://bastola.org/userfiles/file/69293205137.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cbb94e3266---poxolegirufitiwuvafede.pdfIn PDF document text
    • http://marcth.pl/media/fck/file/xikifor.pdfIn PDF document text
    • http://www.badischer-kunstverein.de/ckfinder/userfiles/files/22566797470.pdfIn PDF document text
    • http://blossomtour.net/FileData/ckfinder/files/20210924_2BEAA18DB8543C5B.pdfIn PDF document text
    • http://zhouzhuank.com/v15/Upload/file/202192367215684.pdfIn PDF document text
    • https://kolkataangikar.org/ckfinder/userfiles/files/xogilivu.pdfIn PDF document text
    • http://firsttimehomebuyerstudy.com/images/file/25505106611.pdfIn PDF document text
    • https://cincia.ro/ckfinder/userfiles/files/13484796337.pdfIn PDF document text
    • http://showplus.ae/userfiles/files/28157739631.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/762da89daab654ac2cb82aa55d05fe69/38822612697.pdfIn PDF document text
    • https://tutorbolivia.com/userfiles/file/borilalefoso.pdfIn PDF document text
    • http://www.ishvani.com/www/js/ckfinder/userfiles/files/67650681894.pdfIn PDF document text
    • http://kagoshimakojintaxi.com/userfiles/file/93980414003.pdfIn PDF document text
    • http://mopron.ru/upload/files/18400241860.pdfIn PDF document text
    • https://houstoncoinshow.org/FCKeditor/file/87753891568.pdfIn PDF document text
    • http://lmnn.ru/userfiles/file/xemoxufitomuxigodiduwu.pdfIn PDF document text
    • https://conexkarvan.com/cache/fck_files/file/87872656507.pdfIn PDF document text
    • http://hc6999.com/userfiles/files/zimik.pdfIn PDF document text
    • http://quatangsongvan.com/hinhanh_fckeditor/file/xezabevizinolifawabor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=fliz+movies+online+after+we+collidedPDF 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_off0000aeaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAEAA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c6c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6C1 10824 bytes
SHA-256: c0d324244885e302c4d1938f4b4d1b717f9e6427ccbf577677e9b126608289ed
font_02_sfnt_off0000dfd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFD0 16728 bytes
SHA-256: 06f6596da5332cb09525ca52a9035d6895ea089281fc882d8d5a301646a5e12a