Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef05154ba6040dee…

MALICIOUS

PDF

81.8 KB Created: 2021-09-18 04:35:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 01d8af6097d572faf56eedbe1b3222e7 SHA-1: ff93ee1d2a26b4044b513a6b70402a44b1c2b4c1 SHA-256: ef05154ba6040deecc18fe8fbc8bb785b4031b6b1fd911c4ae4a1c895ec3248e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to websites that appear to be compromised 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. While no scripts were explicitly extracted, the nature of the URLs and the PDF structure points towards a phishing or malware distribution campaign, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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
  • 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://chcial.ru/uplcv?utm_term=el+mejor+juego+de+yu+gi+oh+para+android PDF link annotation
    • http://yjbiotech.cn/upload/files/60039830011.pdfIn PDF document text
    • http://torremaggiore.sitmap.it/files/files/motifariweridebol.pdfIn PDF document text
    • https://mosallaesf.ir/uploads/ck/files/wunuzasome.pdfIn PDF document text
    • http://kehlux.lu/userfiles/files/53991118411.pdfIn PDF document text
    • https://holyfamilyhospitals.com/ckfinder/userfiles/files/junadonuzigofelotopedag.pdfIn PDF document text
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16135ee3e9e7fc---pikirazogizidagijonubome.pdfIn PDF document text
    • http://theprofitnesstrainers.com/userfiles/file/71412223903.pdfIn PDF document text
    • http://www.psoealora.es/ckfinder/userfiles/files/tadirurukota.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16138faa925193---43887770572.pdfIn PDF document text
    • https://baxsporthorses.com/userfiles/file/86548282621.pdfIn PDF document text
    • http://noithatlekhanh.com/Images_upload/files/19968563997.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/161358fbd8ce24---20726186777.pdfIn PDF document text
    • http://101-games.ru/images/uploads/files/biboxexin.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16138ffaa58a4f---27931692399.pdfIn PDF document text
    • https://psiakocky-potisk.cz/webpagebuilder/ckfinder/userfiles/files/mazurakamudu.pdfIn PDF document text
    • http://hibertek.com/image/files/20210910_220359.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/2e58b64121cdeb9f209e8fed9e1e5359/31070843071.pdfIn PDF document text
    • https://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/31b9c1b74c03a9d7098af736d77f4a7f/wodisufidenixojamutoxun.pdfIn PDF document text
    • https://sweetburden.com/upload/users/files/93457046688.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/446e746d341ac4cfdd0bd17c99df807c/laxutafudegokomaxolod.pdfIn PDF document text
    • https://zaindu.drogomedia.com/files/galeria/files/widisinolulavotamovuvez.pdfIn PDF document text
    • https://sapporopools.com/contents/files/16679382256.pdfIn PDF document text
    • http://redemaisfarma.com/userfiles/file/kupanilatepeposabavijad.pdfIn PDF document text
    • http://www.fred-robin.com/ckfinder/userfiles/files/95236407738.pdfIn PDF document text
    • http://www.europesolidaire.eu/userfiles/files/78008584485.pdfIn PDF document text
    • https://promenade-perpignan.com/userfiles/file/80313231338.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_off0000d5b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5B4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000edcb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDCB 10900 bytes
SHA-256: 8472b300455c6f1b2ac58a4daa535ceb1746d7b1a78b4dc971824d11fa7c2ca5
font_02_sfnt_off00010675.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10675 19580 bytes
SHA-256: 23d045aee3a8e226a7fe76f770ece4a5ad4712a659fd15f8cc0e02ed5ae95d70